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Abstract
Velamentous insertion of the umbilical cord, with a reported incidence of 1% in singleton pregnancies, has been associated with several obstetric complications including fetal growth restriction, prematurity, congenital anomalies, low Apgar scores, fetal bleeding and retained placenta. The aim of this study was to determine the feasibility of identifying velamentous insertion of the umbilical cord during routine obstetric ultrasound.
This was a prospective, cross-sectional ultrasound study in 832 unselected second- and third-trimester singleton pregnancies. Color Doppler ultrasound was routinely performed to identify the placental cord insertion site. The role of three-dimensional (3D) ultrasound in evaluating the placental cord insertion site was also studied in a subset of 50 pregnancies from this population.
The placental cord insertion site was identified in 825/832 (99%) cases. Visualization was not achieved in seven third-trimester pregnancies with a posterior placenta. A velamentous insertion was suspected prenatally in eight cases, seven of which were confirmed after delivery as velamentous and one as markedly eccentric (battledore placenta). 3D ultrasound performed poorly at evaluating placental cord insertion site, being less efficient due to poor-quality resolution and far more time-consuming than the combined use of gray-scale and color Doppler ultrasound.
Velamentous insertion of the umbilical cord can reliably be detected prenatally by gray-scale and color Doppler ultrasound. 3D imaging had limited value in the evaluation of the placental cord insertion site in our subset of patients. Systematic assessment of the placental cord insertion site at routine obstetric ultrasound has the potential of identifying pregnancies with velamentous insertion and, therefore, those at risk for obstetric complications including vasa previa.
... Nomiyama et al (1998) inferred that 100% sensitivity and 99.8% specificity were found in US diagnosis of ACI. 14 In the prospective study by Di Salvo et al, they concluded that US had an overall sensitivity of 69%, specificity of 100%, and accuracy of 91% for detecting ACI. 13 Another prospective study conducted by Sepulveda et al observed that a confident identification of the placental CI site was achieved in 99% of cases. 15 The reason for this accuracy they stated was that all US scans were performed by a single experienced fetal medicine specialist. In our study, the placental CI was documented by a single experienced fetal medicine specialist, which might have improved the sensitivity and specificity. ...
... The results of our study were similar to the studies before. 12,15,16 The average weight of baby born with normal CI was 2.99 AE 0.36, and ACI was 2.7 AE 0.612. Babies with ACI were 200 g smaller when compared with normal CI, which was similar to findings from other studies. ...
Introduction Adequate fetal growth during pregnancy depends upon the normal development and insertion of the umbilical cord. Central/paracentral placental cord insertion is considered normal, while marginal/velamentous cord insertion is considered abnormal. Although the location of placental umbilical cord insertion can be determined by ultrasound (US), it is not included in the routine protocol of a targeted anomaly scan. Through this study, we determined different placental umbilical cord insertion sites by US and categorized them as normal and abnormal, identified the risk factors involved, and evaluated the outcome of pregnancies using standard protocols. The rationale of this study was to identify pregnancies that require frequent monitoring and surveillance for an optimal perinatal outcome.
Methods A prospective cohort study was conducted in a tertiary care hospital for 18 months. A total of 345 pregnant women who attended the antenatal outpatient department between 18 and 22 weeks for targeted imaging for fetal anomalies scan were included in the study after informed consent. Detailed history followed by US documentation of the cord insertion site on the placenta was done and women were followed up throughout pregnancy to look for development of complications including hypertensive disorders, antepartum hemorrhage (APH), and fetal growth restriction (FGR). Intrapartum adverse events like fetal distress and intrapartum hemorrhage were assessed. Confirmation of US findings was done by macroscopic examination of the placenta and measuring the distance between the placental cord insertion and the edge of the placenta. The weight of the placenta was also documented. Newborns were evaluated for adverse outcomes like preterm birth, low birth weight, need for resuscitation, and neonatal intensive care unit (NICU) admission. Follow up of neonates and mothers was done till discharge.
Results Placental cord insertion was accurately determined at the anomaly scan with 100% sensitivity and specificity. The study showed 44 abnormal placental cord insertions (ACIs)—42 had marginal and 2 had velamentous cord insertions. There was a high incidence of ACI noted in women aged more than 28 years, with body mass index of more than 26.38, multiparity, previous history of myomectomy, first trimester miscarriage, and conceived by assisted reproductive technology. Women with ACI had an increased risk of small for gestational age/FGR and APH and had an average baby weight of 2.7 kg, which was 200 g less than babies with normal cord insertion. They also had lower mean Apgar scores at 5 minutes and required resuscitation and NICU admission.
Conclusion Our study concluded that it will be a good practice to document the placental cord insertion during the mid trimester anomaly scan so that we can identify the subset of pregnant women who are prone to develop complications, thereby providing adequate surveillance for an optimal perinatal outcome.
... VCI can be identified prenatally by ultrasonography; Buchanan-Hughes et al 12 reported high accuracy in the second-trimester sonographic detection of VCI. In particular, sensitivity varies between 25% 13 and 100%, 14 and specificity is consistently high (99%−100%). 13,14 Currently, the American Institute of Ultrasound in Medicine simply encourages the identification of an abnormal cord insertion, if feasible, 15 whereas the International Society of Ultrasound in Obstetrics and Gynecology considers the assessment of umbilical cord insertion during the routine mid-trimester scan as optional; however, it states that if VCI is incidentally identified, it should be noted. ...
... In particular, sensitivity varies between 25% 13 and 100%, 14 and specificity is consistently high (99%−100%). 13,14 Currently, the American Institute of Ultrasound in Medicine simply encourages the identification of an abnormal cord insertion, if feasible, 15 whereas the International Society of Ultrasound in Obstetrics and Gynecology considers the assessment of umbilical cord insertion during the routine mid-trimester scan as optional; however, it states that if VCI is incidentally identified, it should be noted. 16 To date, there has been no consensus on the inclusion of routine screening for VCI nor a recommended management strategy when VCI is diagnosed antenatally. ...
Introduction
: Velamentous cord insertion (VCI) may be identified prenatally, but the clinical implications of this diagnosis remain controversial. The aim of this meta-analysis was to quantitively summarize current data on the association of VCI and adverse perinatal outcomes.
Data sources
: A systematic search was performed in Medline, Scopus, and the Cochrane Library as of 22nd May 2022 to identify eligible studies.
Study eligibility criteria
: Observational studies including singleton pregnancies with VCI, either prenatally or postnatally identified, and comparing them to those with central/eccentric cord insertion (CCI) were considered eligible.
Study appraisal and synthesis methods
: The quality of the studies was assessed with the Newcastle-Ottawa scale and the risk of bias with the QUIPS tool. The main outcome was small for gestational age neonates. Heterogeneity of the studies was evaluated using a Q test and an I² index. Analyses were performed using a random-effects model with outcome data reported as relative risk or mean difference with 95% confidence interval.
Results
: In total, nine cohort and two case-control studies, of which four with prenatal and seven with postnatal VCI diagnosis, were included. The overall prevalence of VCI was estimated to be 1.4% among singleton pregnancies. Compared to the CCI control group, pregnancies with VCI were at higher risk of several adverse perinatal outcomes, namely small for gestational age (SGA) neonates (RR: 1.93; CI: 1.54-2.41), preeclampsia (RR: 1.85; CI: 1.01-3.39), pregnancy induced hypertension (RR: 1.58; CI: 1.46-1.70), stillbirth (RR: 4.12; CI: 1.92-8.87), placental abruption (RR: 2.94; CI: 1.72-5.03), preterm delivery (RR: 2.14; CI: 1.73-2.65), emergency cesarean delivery (RR: 2.03; CI: 1.22-3.38), 1-min Apgar score <7 (RR: 1.53; CI: 1.14-2.05), 5-min Apgar score <7 (RR: 1.97; CI: 1.43-2.71) and neonatal intensive care unit admission (RR: 1.63; CI: 1.32-2.02). In a sub-group analysis, prenatally diagnosed VCI was associated with SGA (RR: 1.66; CI: 1.19-2.32), stillbirth (RR: 4.78; CI: 1.42-16.08) and preterm delivery (RR: 2.69; CI: 2.01-3.60). In a sensitivity analysis of studies excluding cases with vasa previa, VCI was associated with an increased risk of SGA (RR: 2.69; CI: 1.73-4.17), pregnancy induced hypertension (RR: 1.94; CI: 1.24-3.01) and stillbirth (RR: 9.42; CI: 3.19-27.76), but not preterm delivery (RR: 1.92; CI: 0.82-4.54).
Conclusions
: VCI is associated with several adverse perinatal outcomes, including stillbirth and these associations persist when only prenatally diagnosed cases are considered and when vasa previa cases are excluded. According to these findings, the exact pathophysiology should be further investigated and an effective prenatal monitoring plan should be developed.
... CFI can be used to identify the presence and direction of blood flow, assess the anatomy of the fetal heart and peripheral vessels, and provide a beam/vessel angle correction for a proper measurement of velocity [1]. The addition of CFI to gray-scale ultrasonography can improve the prenatal diagnosis of, among others, heart defects, umbilical cord abnormalities, and placental disorders [2][3][4][5][6][7]. The conventional CFI modes include color Doppler flow imaging (CDFI) and power Doppler imaging (PDI). ...
... CFI is commonly used to evaluate the anatomy and blood flow of the fetal heart, the peripheral vessels, umbilical cord, and the placenta [1][2][3][4][5][6][7]. CFI is also helpful in the evaluation of various structures in the first trimester and in twin pregnancies [9,24]. ...
Color flow imaging (CFI), being non-invasive, is commonly used in obstetrics to study the fetal and placental circulations. The conventional CFI modes include color Doppler flow imaging (CDFI) and power Doppler imaging (PDI). In recent years, there is increasing use of new modes, including high-definition flow imaging (HDFI), radiant flow, microvascular flow imaging (MVFI), and three-/four-dimensional rendering in glass-body mode. Compared to CDFI, HDFI can show a higher resolution and sensitivity and allow the detection of slower flows. MVFI increases the sensitivity to fine or low-flow vessels while producing little or no motion artifacts. Radiant flow shows the blood flow with a sense of depth and reduces blood overflow. Glass-body mode, showing both gray-scale and color-flow information, can demonstrate the heart-cycle-related flow events and the vessel spatial relationship. In this review, the characteristics and applications of the various CFI modes in obstetrics are discussed. In particular, how these new technologies are integrated in detailed diagnostic and early morphology scans is presented.
... Velamentous cord insertion is one of the most undiagnosed conditions in obstetrics. The velamentous cord insertion can be diagnosed by ultrasound, with a sensitivity of 69% to 100% and a specificity of 95% to 100%, in the second trimester [24]. In the third trimester, this condition is also reflected through variable decelerations and abnormal fetal heart rate variability in a non-stress test; this is frequently associated with vasa praevia, the most reliable method of diagnosis for which is the real-time color Doppler transvaginal ultrasound examination, which can depict the umbilical vessel pathway, which crosses the internal os or passes at less than 2 cm from it; this is used to study the enddiastolic velocity of the umbilical artery. ...
... The main risk associated with this abnormality is the rupture of vessels, even without rupture of the membranes resulting in fetal exsanguination or compression by the fetal presentation part. The antenatal diagnosis of vasa praevia increases the neonatal survival from 44% to 97% and improves the neonatal outcome [24,74]. Management particularities include a non-stress examination twice a week after 28 weeks of gestation, and cesarean delivery between 34-36 weeks of gestation [30]. ...
Umbilical cord abnormalities are not rare, and are often associated with structural or chromosomal abnormalities, fetal intrauterine growth restriction, and poor pregnancy outcomes; the latter can be a result of prematurity, placentation deficiency or, implicitly, an increased index of cesarean delivery due to the presence of fetal distress, higher admission to neonatal intensive care, and increased prenatal mortality rates. Even if the incidence of velamentous insertion, vasa praevia and umbilical knots is low, these pathologies increase the fetal morbidity and mortality prenatally and intrapartum. There is a vast heterogeneity among societies’ guidelines regarding the umbilical cord examination. We consider the mandatory introduction of placental cord insertion examination in the first and second trimester to practice guidelines for fetal ultrasound scans. Moreover, during the mid-trimester scan, we recommend a transvaginal ultrasound and color Doppler assessment of the internal cervical os for low-lying placentas, marginal or velamentous cord insertion, and the evaluation of umbilical cord entanglement between the insertion sites whenever it is incidentally found. Based on the pathological description and the neonatal outcome reported for each entity, we conclude our descriptive review by establishing a new, clinically relevant classification of these umbilical cord anomalies.
... Seven publications identified in this review reported the accuracy of second-trimester TAS for diagnosing VCI [16,[63][64][65][66][67][68]. Hasegawa's 2006 report [69] is based on a cohort that overlaps with their 2005 report [65]; therefore, the 2006 report was included in the evidence synthesis to evaluate TAS test accuracy, but the 2005 publication was not considered further. ...
... However, there was considerable variation in sensitivity between studies (between 25 and 100%); the largest and highest quality study reported a low sensitivity of 62.5% [69]. Two of the 3 studies reporting a sensitivity of 100% used TVS when TAS was insufficient, meaning that the sensitivity of TAS alone could not be determined in these cases [67,68]. One study reported that although researchers were reliably able to detect an abnormal cord insertion, the accuracy of diagnosing the specific type of abnormality (MCI vs VCI) was lower [63]. ...
Background:
Velamentous cord insertion (VCI) is an umbilical cord attachment to the membranes surrounding the placenta instead of the central mass. VCI is strongly associated with vasa praevia (VP), where umbilical vessels lie in close proximity to the internal cervical os. VP leaves the vessels vulnerable to rupture, which can lead to fatal fetal exsanguination. Screening for VP using second-trimester transabdominal sonography (TAS) to detect VCI has been proposed. We conducted a rapid review investigating the quality, quantity and direction of evidence available on the epidemiology, screening test accuracy and post-screening management pathways for VCI.
Methods:
MEDLINE, Embase and the Cochrane Library were searched on 5 July 2016 and again on 11 October 2019, using general search terms for VP and VCI. Only peer-reviewed articles reporting on the epidemiology of VCI, the accuracy of the screening test and/or downstream management pathways for VCI pregnancies were included. Quality and risk of bias of each included study were assessed using pre-specified tools.
Results:
Forty-one relevant publications were identified; all but one were based on non-UK pregnancy cohorts, and most included relatively few VCI cases. The estimated incidence of VCI was 0.4-11% in singleton pregnancies, with higher incidence in twin pregnancies (1.6-40%). VCI incidence was also increased among pregnancies with one or more other risk factors, including in vitro fertilisation pregnancies or nulliparity. VCI incidence among women without any known risk factors was unclear. VCI was associated with adverse perinatal outcomes, most notably pre-term birth and emergency caesarean section in singleton pregnancies, and perinatal mortality in twins; however, associations varied across studies and the increased risk was typically low or moderate compared with pregnancies without VCI. In studies on limited numbers of cases, screening for VCI using TAS had good overall accuracy, driven by high specificity. No studies on post-screening management of VCI were identified.
Conclusions:
Literature on VCI epidemiology and outcomes is limited and low-quality. The accuracy of second-trimester TAS and the benefits and harms of screening cannot be determined without prospective studies in large cohorts. Modelling studies may indicate the feasibility and value of studying the epidemiology of VCI and the potential impact of detecting VCI as part of a population screening programme for VP.
... Gianopoulos et al. [5] described in 1987 for the first time the ultrasonographic diagnosis of vasa previa, and since then changed the poor prognosis of these pregnancies. From that peculiar moment on, several small case series proved the ability of ultrasonography and color Doppler to improve these pregnancies outcome [6,7], based on early prenatal diagnosis and proper intervention by cesarean delivery prior to the onset of labour. ...
... Since first reported in the literature by Lobstein in 1801 [8], Gianopoulos et al. [5] first described in 1987 the diagnosis of vasa previa using ultrasound, then early and mid 1990 several authors reported sonographic diagnosis of vasa previa (2D and 3D, colour flow Doppler) resulting in promising perinatal outcomes [9,10]. At this point, it wasn't well established the moment during pregnancy when the diagnosis became possible, ranging from late in the first trimester to term [4,7]. ...
... When performed by a trained operator, screening and diagnosis of cord insertion abnormalities is highly accurate, with a detection rate of around 99 % [20,24,37,38]. Transvaginal sonography is essential for the diagnosis of VP, and together with colour Doppler it diagnosed all cases of VP during the second trimester (sensitivity, 100 %) with a specificity of 99.0-99.8 ...
... 1e3 However, there are data supporting universal vasa previa screening because it is feasible without requiring additional personnel, time, and equipment beyond what is used in routine obstetrical ultrasound. 31,51,52 Given the high perinatal mortality associated with vasa previa undiagnosed before birth, the high detection rate of ultrasound for the condition, and the dramatic reduction in perinatal mortality accompanying prenatal diagnosis, several authors have argued for universal screening for the condition. 4,8,23,31,53 The panel also agreed that transvaginal ultrasound screening should be performed routinely in patients with risk factors for vasa previa (second-trimester low-lying placenta and placenta previa, velamentous cord insertion, multifetal pregnancies, pregnancies with accessory lobes). ...
... Second-trimester TAS has been reported to have consistently high specificity (>99.8%) [23][24][25]. In the largest and highest-quality study, sensitivity was reported to be 62.5%, specificity 100%, positive predictive value 83%, negative predictive value 100%, and accuracy 99.8% [25]. ...
Background:
The effect of velamentous cord insertion (VCI) on perinatal outcomes in twin pregnancies is unclear due to conflicting findings. This retrospective study aimed to examine VCI prevalence and related risk factors in twin pregnancies and its association with adverse perinatal outcomes.
Methods:
Women with twin pregnancies who delivered between January 2012 and December 2021 in a single tertiary hospital were included. The participants were divided into dichorionic (DC) and monochorionic diamniotic (MCDA) groups, and their maternal and fetal characteristics and VCI rates were compared. Logistic regression models were used to identify risk factors for VCI and VCI-related perinatal outcomes.
Results:
Among the 694 twin pregnancies included in this study, the VCI rate was significantly higher in MCDA than in DC twins. Body mass index and MCDA twins were significant risk factors for VCI, whereas assisted reproductive technology pregnancy was a significant protective factor against VCI. In DC twins, VCI did not affect perinatal outcomes. In MCDA twins, VCI was a significant risk factor for fetal growth restriction, twin-to-twin transfusion syndrome, and preterm birth at <36 weeks.
Conclusions:
VCI was a prominent risk factor for adverse perinatal outcomes only in MCDA twins. Antenatal sonographic assessment of the umbilical cord insertion site would be beneficial.
... 7,38,42,46,67 A study by Nomiyama et al 75 demonstrated that routine ultrasound examination for placental cord insertion was accurate and achievable in less than 1 minute in 95% of examinations. Another study by Sepulveda et al 76 confirmed that routine evaluation of placental cord insertion is feasible as a part of the second-trimester anatomy scan. ...
Vasa previa refers to unprotected fetal vessels running through the membranes over the cervix. Until recently, this condition was associated with an exceedingly high perinatal mortality rate attributable to fetal exsanguination when the membranes ruptured. However, ultrasonography has made it possible to diagnose the condition prenatally, allowing cesarean delivery before labor or rupture of the membranes. Several recent studies have indicated excellent outcomes with prenatally diagnosed vasa previa. However, outcomes continue to be dismal when vasa previa is undiagnosed before labor. Risk factors for vasa previa include second-trimester pla-centa previa and low-lying placentas, velamentous cord insertion, placentas with accessory lobes, in vitro fertilization, and multifetal gestations. Recognition of individuals who are at risk and screening them will greatly decrease the mortality rate from this condition. Because of the relative rarity of vasa previa, there are no randomized controlled trials to guide management. Therefore, recommendations on the diagnosis and management of vasa previa are based largely on cohort studies and expert opinion. This Clinical Expert Series review addresses the epidemiology , pathophysiology, natural history, diagnosis and management of vasa previa, as well as innovative treatments for the condition.
... Spontaneous UCVR has no speci c clinical symptoms and is often secondary to velamentous insertion [9], shortness and damage of the umbilical cord, and rupture of the membranes [10]. It is therefore di cult to distinguish between placental abruption and other conditions that can cause fetal distress.And it is hard to diagnosis before labour.Prenatal color ultrasound may be the best way to screen for prenatal risk factors such as abnormal umbilical cord insertion and amniotic uid.The detection rate of the umbilical cord attachment site is closely related to gestational age, with about 67% being diagnosed at 15-20 weeks of gestation and 30% at 36-40 weeks of gestation [11]. ...
Background
Spontaneous umbilical cord vascular rupture(UCVR)is a rare but catastrophic event, and may lead to fetal blood loss and severe perinatal morbidity and mortality. UCVR remains difficult to diagnose, so when it happen, the effective treatment is a key to improve the pregnancy outcomes.UCVR as an obstetric emergency situation especially for neonate, whether rapid response team(RRT) could have effectiveness on the pregnancy outcomes is rare reported.
Methods
A retrospective cohort study of twelve patients with spontaneous UCVR from 2012 to 2022 were undertaken. Data and images of UCVR were collected via the electronic case system.Demographic and clinical characteristics were collected by researchers.
Results
Twelve patients were diagnosed by postpartum placental examination and pathological examination. The mean age of participants was (29.67 ± 3.75) years, the mean BMI was (20.48 ± 2.43)kg/m², the mean gestational age at which rupture occurred was (37.33 ± 2.61)weeks. The decision to delivery interval(DDI) was from 5 to 15 minutes.2 of them were marginal umbilical cord insertion, 5 were velamentous insertion. 9 cases were bloody amniotic fluid. Although all the umbilical cord lengths were within the normal range (38–70 cm), 5 had the umbilical cord around their necks. 10 were vein rupture, 1 was artery and 1 was both atery and vein rupture. About the pregnancy complications, mainly complicated with fetal distress,premature rupture of the membranes(PROM) ,anemia, velamentous cord insertion(VCI), GDM and racket placenta. 6 of them with abnormal placental insertion. all the neonates were admitted to the neonatal intensive care unit (NICU)for 1 to 63 days. Except for one case of stillbirth during the vaginal labour, there were 11 livebirths who underwent cesarean section. One died two days after birth due to severe complications.They were mainly complicated with hypoxic ischemic encephalopathy(HIE),severe neonatal asphyxia and neonatal pneumonia. But with a well prognosis after more than 1 year’s follow-up.
Conclusions
Early identification of spontaneous UCVR by FHR and character of amniotic fluid during labour is important. Once vascular rupture occurs, obstetric RRT should be activated and the emergency CS should be performed with shorter DDI to reduce perinatal mortality.
... Sin embargo, la ecografía de rutina a menudo no detecta la IV y no se recomienda un cribado ecográfico universal, pudiéndose realizar en los casos que existan factores de riesgo prenatal (5) . La identificación prenatal IV es un objetivo clínico deseable, ya que estos embarazos tienen un mayor riesgo de resultados perinatales adversos y, a pesar de la importancia obvia de la detección prenatal de la IV en la práctica obstétrica, solo unos pocos estudios se han centrado en la identificación sistemática del sitio de inserción del cordón placentario durante la ecografía prenatal (16) . ...
La afección vasa previa es un hallazgo prenatal raro y poco frecuente de hemorragiaen la segunda mitad del embarazo, en la que los vasos umbilicales desprovistos dela gelatina de Wharton se interponen entre la presentación fetal y el orificio cervicalinterno. Cuando no se la detecta y se produce la rotura de los vasos, se asocia auna alta tasa de mortalidad perinatal. Se describen 3 tipos; el caso presentado setrata de vasa previa de tipo 1 secundaria a inserción velamentosa de cordón. Fuediagnosticada prenatalmente mediante ecografía por vía transvaginal asociada aDoppler color. Se practicó una cesárea con evolución materno perinatal favorable.
... Notwithstanding, this adverse obstetric outcome could inevitably pose potential risks to both mothers and their children. For instance, an aberrant condition of the umbilical cord may have detrimental influences on the fetus, such as fetal growth restriction, preterm birth, and stillbirth [32][33][34][35]. To that extent, it is worthy of close attention in further studies. ...
Abstract Background With the wide application of preimplantation genetic testing (PGT) with trophectoderm (TE) biopsy, the safety of PGT has always been a concern. Since TE subsequently forms the placenta, it is speculated that the removal of these cells was associated with adverse obstetrical or neonatal outcomes after single frozen-thawed blastocyst transfer (FBT). Previous studies report contradictory findings with respect to TE biopsy and obstetric and neonatal outcomes. Methods We conducted a retrospective cohort study including 720 patients with singleton pregnancies from single FBT cycles who delivered at the same university-affiliated hospital between January 2019 and March 2022. The cohorts were divided into two groups: the PGT group (blastocysts with TE biopsy, n = 223) and the control group (blastocysts without biopsy, n = 497). The PGT group was matched with the control group by propensity score matching (PSM) analysis at a ratio of 1:2. The enrolled sample sizes in the two groups were 215 and 385, respectively. Results Patient demographic characteristics were comparable between the groups after PSM except for the proportion of recurrent pregnancy loss, which was significantly higher in the PGT cohort (31.2 vs. 4.2%, P
... It is a common practice to add color flow imaging (CFI) to gray-scale ultrasonography in obstetric scans to detect abnormal blood flow in fetal and placental abnormalities [1][2][3][4][5][6][7]. Various CFI modes were discussed in a recent review by Leung KY [8]. ...
Using color Doppler flow imaging or high-definition flow imaging with three-dimensional volume or spatio-temporal image correlation (STIC) in the glass-body mode allows displaying both gray-scale and color information of the heart cycle-related flow events and vessel spatial relationship. Conventionally, STIC in the glass-body mode has been used to examine the fetal heart and assess heart defects. Recently, a novel application of STIC in the visualization of abdominal precordial veins and intraplacental vascularization in singleton pregnancies has been reported. The aim of this present review is to discuss the use of color Doppler with three- and four-dimensional ultrasonography in the evaluation of extracardiac, placental, umbilical cord and twin abnormalities with examples. The glass-body mode is complementary to conventional 2D ultrasonography. Further studies are required to investigate use of the glass-body mode in the assessment of intraplacental vascularization in singleton and twin pregnancies.
... ACI has been associated with small-for-gestational age fetuses. This is probably because eccentric cord insertion causes unequal chorionic vascular distribution in the placenta, possibly leading to reduced and inefficient fetoplacental circulation [1,7,[26][27][28][29]. It is reasonable to assume that ACI is related to NRFS during labor, because an abnormally inserted umbilical cord tends to be vulnerable to compression during labor, especially after rupture of the membranes and/or the presenting components have descended, compared with normally inserted cords [30][31][32]. ...
Objective: We elucidated maternal background, perinatal complications and outcomes as potential related factors for abnormal umbilical cord insertion (ACI) -velamentous and marginal- based on data from two tertiary perinatal hospitals in Japan.
Materials and Methods: The subjects were 3,741 women with singleton pregnancies who delivered at ≥ 22 weeks’ gestation in Kurume University Hospital and St. Mary’s Hospital, Kurume, Japan from January 2013 to December 2015. They were divided into two groups, with and without ACI. Related factors were extracted from the medical registry database of the perinatal committee in the Japan Society of Obstetrics and Gynecology. Random Forest and stepwise logistic regression models were employed to evaluate their impact on ACI.
Results: Related factors for ACI in terms of maternal background and perinatal complications and outcomes were: pre-pregnancy smoking habit (adjusted odds ratio, OR, 3.38; 95% confidence interval, CI, 2.20–5.20; P < 0.0001); conception using assisted reproductive technology (adjusted OR, 2.00; 95% CI, 1.11–3.60; P = 0.021); placenta previa (adjusted OR, 4.74; 95% CI, 2.06–10.90; P < 0.0001); fetal growth restriction (adjusted OR, 2.43; 95% CI, 1.49–3.97; P < 0.0001); and non-reassuring fetal status during labor (adjusted OR, 2.74; 95% CI, 1.71–4.38; P < 0.0001).
Conclusion: This was a preliminary study attempting to elucidate related factors for ACI in a Japanese population. However, further large-scale studies are needed in Japan.
... Notwithstanding, these two adverse obstetric outcomes could inevitably pose potential risks to both mothers and their children. For instance, an aberrant condition of the umbilical cord may have detrimental in uences on the fetus, such as fetal growth restriction, preterm birth, and stillbirth [32][33][34][35]. To that extent, it is worthy of close attention in further studies. ...
Background: With the wide application of preimplantation genetic testing (PGT) with trophectoderm (TE) biopsy, the safety of PGT has always been a concern. Since TE subsequently forms the placenta, it is speculated that the removal of these cells was associated with adverse obstetrical or neonatal outcomes after single frozen-thawed blastocyst transfer (FBT). Previous studies report contradictory findings with respect to TE biopsy and obstetric and neonatal outcomes.
Methods: We conducted a retrospective cohort study including 720 patients with singleton pregnancies from single FBT cycles who delivered at the same university-affiliated hospital between January 2019 and March 2022. The cohorts were divided into two groups: the PGT group (blastocysts with TE biopsy, n=223) and the control group (blastocysts without biopsy, n=497). The PGT group was matched with the control group by propensity score matching (PSM) analysis at a ratio of 1:2. The enrolled sample sizes in the two groups were 215 and 385, respectively.
Results: Patient demographic characteristics were comparable between the groups after PSM. Patients in the PGT group had significantly higher rates of hypertensive disorders of pregnancy (HDP) (13.5 vs. 8.8%, adjusted odds ratio (aOR) 1.76, 95% confidence interval (CI) 1.02–3.05, P = 0.043), gestational hypertension (6.0 vs. 2.6%, aOR 2.65, 95% CI 1.12–6.30, P = 0.027) and abnormal umbilical cord (13.0 vs. 7.8%, aOR 1.83, 95% CI 1.05–3.17, P = 0.032). However, the occurrence of premature rupture of membranes (PROM) (12.1 vs. 19.7%, aOR 0.57, 95% CI 0.35–0.93, P = 0.025) was significantly lower in biopsied blastocysts than in unbiopsied embryos. There were no significant differences in regard to other obstetric and neonatal outcomes between the two groups.
Conclusions: Trophectoderm biopsy is a safe approach, as the neonatal outcomes from biopsied and unbiopsied embryos were comparable. Furthermore, PGT is associated with higher risks of HDP, gestational hypertension, and abnormal umbilical cord but has a protective effect on PROM.
... PPH due to retention of placenta or membranes was related to velamentous and marginal umbilical cord insertion in a dose-response-pattern with strongest association to velamentous insertion. Both conditions are possible to diagnose by ultrasonography during pregnancy [57]. ...
Objective:
To explore risk profiles of the different types of postpartum hemorrhage (PPH >500ml or severe PPH >1500ml) and their recurrence risks in a subsequent delivery.
Methods:
With data from The Medical Birth Registry of Norway and Statistics Norway we performed a population-based cohort study including all singleton deliveries in Norway from 1967-2017. Multilevel logistic regression was used to calculate odds ratio (OR), with 95% confidence interval (CI), with different PPH types (PPH >500ml or PPH >1500ml (severe PPH) combined with retained placenta, uterine atony, obstetric trauma, dystocia, or undefined cause) as outcomes.
Result:
We identified 277 746 PPH cases of a total of 3 003 025 births (9.3%) from 1967 to 2017. Retained placenta (and/or membranes) was most often registered as severe PPH (29.3%). Maternal, fetal, and obstetric characteristics showed different associations with the PPH types. Male sex of the neonate was associated with reduced risk of PPH. This effect was strongest on PPH due to retained placenta (adjusted OR, (aOR): 0.80, 95% CI 0.78-0.82), atony (aOR 0.92, 95% CI: 0.90-0.93) and PPH with undefined cause (aOR 0.96, 95% CI: 0.95-0.97). Previous cesarean section showed a strong association with PPH due to dystocia (aOR of 13.2, 95% CI: 12.5-13.9). Recurrence risks were highest for the same type: PPH associated with dystocia (aOR: 6.8, 95% CI: 6.3-7.4), retained placenta and/or membranes (aOR: 5.9, 95% CI: 5.5-6.4), atony (aOR: 4.0, 95% CI: 3.8-4.2), obstetric trauma (aOR: 3.9, 95% CI: 3.5-4.3) and PPH of undefined cause (aOR: 2.2, 95% CI: 2.1-2.3).
Conclusion:
Maternal, fetal and obstetric characteristics had differential effects on types of PPH. Recurrence differed considerably between PPH types. Retained placenta was most frequently registered with severe PPH, and showed strongest effect of sex; delivery of a boy was associated with lower risk of PPH. Previous cesarean increased the risk of PPH due to dystocia.
... Color Doppler ultrasound is a noninvasive diagnostic method for clinical diagnosis of obstetrics and gynecology diseases, which can be used to detect blood flow signals and highlight the umbilical vessel pathway [9,13], which have proven to be valuable antepartum diagnostic tools for the early recognition of VP [14]. Moreover, ultrasound used color Doppler had a 74.1% sensitivity for the diagnosis of VCI with a positive predictive value (PPV) of 90.9% [15,16], which was reported to have increased sensitivity to 100% with a lower PPV (85.7%) after the limited analysis by Rodriguez D et al. [17]. Currently, transabdominal color Doppler ultrasonography (TA-CDUS) and transvaginal color Doppler ultrasonography (TV-CDUS) are both used in the clinical diagnosis of several diseases, such as uterine adenomyoma and uterine fibroids [18], endometrial polyps [19], and ventriculo-coronary communications [20]. ...
Objective:
The objective of this study is to evaluate feasibility and accuracy of transabdominal color Doppler ultrasound (TA-CDUS) and transvaginal color Doppler ultrasound (TV-CDUS) as screening methods for pregnant women with vasa previa (VP) and velamentous cord insertion (VCI).
Methods:
A retrospective diagnostic accuracy study was performed on 5,434 pregnant women from 2018 to 2021, who underwent both TA-CDUS and TV-CDUS. Diagnostic performance of TA-CDUS and TV-CDUS was determined using specificity, positive predictive value (PPV), negative predictive value (NPV), accuracy, and positive and negative likelihood ratios (LR+ and LR-), using the delivery information (gross examination) as the "Gold-standard". Patient records were reviewed for demographics and diagnosis.
Results:
The combination of VP and VCI was diagnosed in 37/5434 (0.68%) women at delivery. The sensitivity, specificity, PPV, NPV, and overall test accuracy of TA-CDUS were 72.97%, 99.85%, 77.14%, 99.81%, and 99.67%, respectively, for diagnosing VP with VCI. The corresponding values for TV-CDUS were 89.19%, 99.87%, 82.50%, 99.93%, and 99.80%, respectively. Moreover, the sensitivity of combination of TA-CDUS and TA-CDUS in determining VP with VCI was 97.30%, specificity 99.98%, PPV 97.30%, NPV 99.98%, and accuracy 99.96%. No significant difference in the misdiagnosis and missed diagnosis was found between the examination by TA-CDUS and TV-CDUS.
Conclusions:
Both TA-CDUS and TV-CDUS can be acceptable diagnostic tools for assessment of pregnant women with VP and VCI, with a better application of TV-CDUS with higher accuracy. The combination of TA-CDUS and TV-CDUS could provide an objective imaging basis for choosing clinical treatment strategies and predicting prognosis.
... VCI is characterized by membranous cord vessels at the cord insertion site [2] and its estimated prevalence has been reported to be approximately 1%. Several studies have shown that VCI is associated with increased adverse obstetric outcomes, such as preterm birth (PTB), increased rate of cesarean deliveries (CD), and small for gestational age (SGA) status [3,4]. Nevertheless, the results of previous studies that examined the association between MCI and obstetric outcomes were inconsistent [1,[5][6][7]. ...
Abnormal cord insertion (ACI) is associated with adverse obstetric outcomes; however, the relationship between ACI and assisted reproductive technology (ART) has not been examined in a meta-analysis. This study examines the association between ACI and ART, and delivery outcomes of women with ACI. A systematic review was conducted, and 16 studies (1990–2021) met the inclusion criteria. In the unadjusted pooled analysis (n = 10), ART was correlated with a higher rate of velamentous cord insertion (VCI) (odds ratio (OR) 2.14, 95% confidence interval (CI) 1.64–2.79), marginal cord insertion (n = 6; OR 1.58, 95%CI 1.26–1.99), and vasa previa (n = 1; OR 10.96, 95%CI 2.94–40.89). Nevertheless, the VCI rate was similar among the different ART types (blastocyst versus cleavage-stage transfer and frozen versus fresh embryo transfer). Regarding the cesarean delivery (CD) rate, women with VCI were more likely to have elective (n = 3; OR 1.13, 95%CI 1.04–1.22) and emergent CD (n = 5; OR 1.93, 95%CI 1.82–2.03). In conclusion, ART may be correlated with an increased prevalence of ACI. However, most studies could not exclude confounding factors; thus, further studies are warranted to characterize ART as a risk factor for ACI. In women with ACI, elective and emergent CD rates are high.
... The results were compared with the study made by Manikanta etal (8) , Sepulveda etal (9) ,Donald etal (10) and Roma patel etal (11) . The observations correlated with these studies. ...
Umbilical cord shows variations in its insertion at the placenta. This reflects the underlying modifications of fetal circulation in the intrauterine life. Knowledge regarding the prevalence of variations in the umbilical cord insertion is essential for obstetricians and peadiatricians to predict the developmental abnormalities in fetal circulation. The present study was done to evaluate the various types of umbilical cord insertions encountered in the human placentae delivered in a tertiary care hospital. 80 placentae with umbilical cords were collected for 6 months from the hospital with the concerned permissions. They were washed thoroughly and fixed in 10% formalin for preservation. Each placenta was observed carefully for the umbilical cord insertion. The results were analysed and represented graphically. There were no considerable knots observed in the stumps of the cords. All the cords had normal three vessels on cross-section i.e., two umbilical arteries and one umbilical vein. When the patterns of insertions were examined, 71% showed normal central insertion, 29% were abnormal where 19% marginal, 7% furcate and 3% exhibited velamentous insertion. When compared with other studies, they correlated. The present study depicts the various abnormal types of umbilical cord insertions from the human placentae collected from a tertiary care hospital.
... 110,111 Following utilization of color Doppler imaging, the sensitivity and specificity of prenatal sonographic diagnosis of this condition have improved considerably and range between 69% and 100% and between 95% and 100%, respectively. [112][113][114][115] Velamentous Insertion in Twins ...
The umbilical cord constitutes a continuation of the fetal cardiovascular system anatomically bridging between the placenta and the fetus. This structure, critical in human development, enables mobility of the developing fetus within the gestational sac in contrast to the placenta, which is anchored to the uterine wall. The umbilical cord is protected by unique, robust anatomical features, which include: length of the umbilical cord, Wharton’s jelly, two umbilical arteries, coiling, and suspension in amniotic fluid. These features all contribute to protect and buffer this essential structure from potential detrimental twisting, shearing, torsion, and compression forces throughout gestation, and specifically during labor and delivery. The arterial components of the umbilical cord are further protected by the presence of Hyrtl’s anastomosis between the two respective umbilical arteries. Abnormalities of the umbilical cord are uncommon yet include excessively long or short cords, hyper or hypocoiling, cysts, single umbilical artery, supernumerary vessels, rarely an absent umbilical cord, stricture, furcate and velamentous insertions (including vasa previa), umbilical vein and arterial thrombosis, umbilical artery aneurysm, hematomas, and tumors (including hemangioma angiomyxoma and teratoma). This commentary will address current perspectives of prenatal sonography of the umbilical cord, including structural anomalies and the potential impact of future imaging technologies.
... The results were compared with the study made by Manikanta etal (8) , Sepulveda etal (9) ,Donald etal (10) and Roma patel etal (11) . The observations correlated with these studies. ...
Umbilical cord shows variations in its insertion at the placenta. This reflects the underlying modifications of fetal circulation in the intrauterine life. Knowledge regarding the prevalence of variations in the umbilical cord insertion is essential for obstetricians and peadiatricians to predict the developmental abnormalities in fetal circulation. The present study was done to evaluate the various types of umbilical cord insertions encountered in the human placentae delivered in a tertiary care hospital. 80 placentae with umbilical cords were collected for 6 months from the hospital with the concerned permissions. They were washed thoroughly and fixed in 10% formalin for preservation. Each placenta was observed carefully for the umbilical cord insertion. The results were analysed and represented graphically. There were no considerable knots observed in the stumps of the cords. All the cords had normal three vessels on cross-section i.e., two umbilical arteries and one umbilical vein. When the patterns of insertions were examined, 71% showed normal central insertion, 29% were abnormal where 19% marginal, 7% furcate and 3% exhibited velamentous insertion. When compared with other studies, they correlated. The present study depicts the various abnormal types of umbilical cord insertions from the human placentae collected from a tertiary care hospital.
... In this study, six patients had cord insertion abnormalities, of which four had velamentous insertion and two had racket placenta. The detection rate of the umbilical cord attachment site is closely related to gestational age, with about 67% being diagnosed at 15-20 weeks of gestation and 30% at 36-40 weeks of gestation [9] . Therefore, screening in the middle of pregnancy is particularly important [10][11][12] . ...
Background: Spontaneous umbilical cord vascular rupture is a rare but catastrophic event during pregnancy, and the perinatal mortality rate is extremely high. Live neonates may have severe asphyxia and require admission to the neonatal intensive care unit for many days.
Methods: A retrospective review of the clinical data of eleven patients with spontaneous umbilical cord vascular rupture from 2012 to 2020, was undertaken at our hospital.
Results: All patients were diagnosed by postpartum placental examination and pathological examination. The Obstetric Rapid Response Team performed emergency cesarean sections in fetal distress patients, and the time between detection of fetal heart abnormality and delivery was 5 to 13 minutes. Eight patients had bloodstained amniotic fluid and one had III° foul amniotic fluid. Six patients had the umbilical cord around their necks. Furthermore, pathological examination of postpartum placentas found four cases of intrauterine infection.Among the eight live neonates, one neonate died two days after birth due to severe complications and one had neonatal hyperbilirubinemia. No neurological sequelae, or other severe complications were found in the remaining seven neonates after three months of follow-up, and all of them had a positive prognosis.
Conclusion: Spontaneous umbilical cord vascular rupture is a serious risk for perinatal birth life and obstetric complications. For this reason, obstetricians should be familiar with and pay attention to its risk factors.
... The examination of placental cord insertion at routine ultrasound examination after 16 gestational weeks is feasible in 95% of all cases in <1 min. 19 Thus, we decided to use the site of placental cord insertion for screening for vasa previa and transvaginal sonography for diagnosis in high-risk groups. The assumption was that it seems unlikely that a central or lateral cord insertion in normal placentas is associated with extraplacental fetal vessels. ...
Introduction:
The presence of vasa previa carries a high risk for severe fetal morbidity and mortality due to fetal bleeding caused by injury to unprotected fetal vessels when rupture of membranes occurs. Previously, it has been shown that prenatal diagnosis significantly improves the outcome. However, systematic screening for vasa previa is not generally performed, and clinical studies demonstrating the performance of systematic screening for vasa previa in routine clinical practice are rare. The objective of this study was to assess the performance of systematic screening for vasa previa by determining placental cord insertion at the 20-week anomaly scan.
Material and methods:
This is a retrospective study of 6038 pregnant women between 18+0 and 24+0 gestational weeks who were prospectively screened for vasa previa by depiction of the site of placental cord insertion on occasion of the 20-week anomaly scan. Pregnancies with marginal or velamentous cord insertion underwent vaginal sonography for examination for vasa previa. In cases with succenturiate or bilobed placentas, the bridging vessels were depicted, and vaginal sonography was performed if necessary.
Results:
There were 21 cases of vasa previa, and all were diagnosed prenatally. In 18 cases, the cord insertion was marginal or velamentous. The remaining three cases had placental anomalies, which necessitated a detailed examination. All pregnancies with vasa previa were delivered at a mean of 35.2 (SD 1.8) gestational weeks by cesarean section. Among pregnancies affected by vasa previa, all fetuses survived. The median birthweight was 2390 g (range 1200 to 2990 g), and the mean umbilical artery pH was 7.34 (SD 0.04). The median five-minute APGAR score was 9 (range 7-10). None of the fetuses or neonates died or required blood transfusions. In all pregnancies of the whole cohort which were complicated by fetal or neonatal demise and in neonates with a 5-minute APGAR score ≤ 5 and/or an umbilical artery pH ≤ 7.10, fetal blood loss was excluded as a cause for the poor obstetric outcome.
Conclusions:
Screening for vasa previa is feasible and efficient, taking into account the site of placental cord insertion in pregnancies not affected by placenta previa and bilobed and succenturiate placenta.
... The prevalence of VCI among the study population was 0.84%; this figure was similar to reported in previous studies. [11] Maternal obesity and fertility problems were associated with an increased prevalence of VCI, which were known to be in constant increase in our catchment area and may thus explain the changes in the prevalence of VCI. [12,13] The mechanism linking obesity and abnormal insertion was beyond the scope of the present study, but maternal obesity may lead to alterations in placental development or function. ...
To identify the risk factors associated with velamentous cord insertion (VCI) and investigate the association between adverse pregnancy outcomes and VCI in singleton pregnancies and those with vasa previa.
A total of 59,976 single cases admitted from Qinhuangdao Maternal and Child Health Hospital and Qinhuangdao Beidaihe Hospital from January 2004 to January 2014 were included in this study. We retrospectively analyzed the perinatal complications, neonatal complications, and the clinical features, as well as the Color Doppler ultrasonography findings of the velamentous placenta and placenta previa.
We reviewed the clinical data of 59,976 women with singleton pregnancies delivered in Qinhuangdao Maternal and Child Health Hospital and Qinhuangdao Beidaihe Hospital from January 2004 to January 2014. Risk factors and the risks of adverse pregnancy outcomes including admission to a neonatal unit, fetal death, preterm delivery, low birth weight of <2500 g, the infant being small for its gestation age, low Apgar scores (<7) at 1 and 5 minute were evaluated separately among women with and without VCI by means of logistic regression analyses.
The prevalence of velamentous umbilical cord insertion was 0.84%, and the prevalence of vasa previa was 0.0017%. The independent risk factors for VCI were nulliparity, obesity, fertility problems, placenta previa, and maternal smoking. VCI was associated with a 1.83-, 2.58-, 3.62-, and 1.41-fold increase in the risk of retention in the neonatal unit, preterm delivery (<37 gestation weeks), low birth weight, and small-for-gestational age, compared to pregnancies involving normal cord insertion. Of the women with VCI, 16.1% underwent emergency cesarean section compared to 8.9% (P < .001) of women without VCI.
The prevalence of VCI was 0.84% in singletons. The results suggest that VCI is a moderate risk condition resulted in increased risks of prematurity and impairment of fetal growth.
... Because ultrasound detection of VP and velamentous cord insertion is more difficult with advanced gestation, ultrasound screening during mid-gestation is recommended. [5][6][7] In fact, diagnoses of VP were made at a median of 26 weeks of gestation and referrals to tertiary hospitals were performed at a median of 28 weeks of gestation in the present study. In the 31 reported cases of VP, 1 case resulted in neonatal death without antenatal diagnosis, and the others were diagnosed antenatally and were birthed successfully. ...
Aim:
This study aimed to clarify ultrasound screening and management for vasa previa (VP) in perinatal centers and primary facilities in Japan.
Methods:
A questionnaire survey about antepartum ultrasound screening and management for VP was delivered in 2018. Questions were sent by email or post to perinatal centers and randomly selected primary hospitals or clinics throughout Japan.
Results:
Seventy-seven perinatal centers and 300 primary facilities answered. VP was screened in 85.7% of perinatal centers and 81.3% of primary facilities. The reported incidence of VP was 0.05% (86/158 323) and 0.05% (28/54 791) in perinatal centers and primary facilities, respectively. When patients were diagnosed with VP, 88.7% of primary facilities referred the patient to a tertiary hospital. Routine hospitalization (100%) and steroid administration (46%) were frequently performed in perinatal centers. The median gestational age at planned cesarean section was significantly earlier in perinatal centers (34 weeks) than in primary facilities (37 weeks). Of the 31 reported cases of VP, 30 were reported as intact survival, but 1 case required an emergency cesarean section at 38 weeks of gestation without an antenatal diagnosis, resulting in neonatal death.
Conclusion:
More than 80% of obstetric facilities both perinatal centers and clinics in Japan perform ultrasound screening with for VP with similar detection rate. However, to further improve perinatal outcomes related to VP, pathophysiology and diagnosis of VP should be more widely recognized by obstetric caregivers throughout Japan.
Introduction/Purpose
It is well‐documented in the literature that the placenta migrates during pregnancy; however, studies regarding placental cord insertion (PCI) migration are scarce. This longitudinal, prospective study aimed to determine whether PCI migration is a true phenomenon, to assess whether the PCI can change classification during pregnancy and to determine the validity of PCI site documentation including follow‐up of abnormal PCI.
Methods
Eighty‐three participants who had first, second and third trimester ultrasound examinations at a Western Australian private imaging practice over a 12‐month period between November 2021 and November 2022 were recruited. The measured distance of the lower margin of the placenta to the cervix, the distance of the PCI to the closest placental edge and the PCI classification were documented in each trimester. Data analysis was conducted to determine PCI migration rates during pregnancy and to test for association between PCI migration and maternal and placental factors.
Results
The PCI migrated during pregnancy and the PCI classification has the potential to evolve. All identifiable PCIs that were normal in first trimester remained so throughout the pregnancy. The majority (67.6%) of cord insertions that were marginal in first trimester progressed to a normal insertion site by third trimester; 23.5% remained marginal and 8.8% evolved to a velamentous insertion. Three velamentous cord insertions were recorded in first trimester, none of which normalised—two remained velamentous during the pregnancy and one evolved to marginal in second trimester. Marginal cord insertions (MCIs) ≤10 mm from the placental edge in second trimester remained marginal in third trimester; MCIs that were >15 mm from the placental edge in second trimester normalised in third trimester.
Conclusions
Placental cord insertion migration is a phenomenon that occurs during pregnancy with the potential for PCI classification to evolve. Due to the association between abnormal PCI and perinatal complications, coupled with the potential for marginal cord insertion to evolve, documentation of PCI and follow‐up of abnormal PCI is beneficial, particularly in cases of velamentous insertion and marginal insertion at the placental edge or in the lower uterus.
Background: The effect of velamentous cord insertion (VCI) on perinatal outcomes in twin pregnancies is unclear due to conflicting findings. This retrospective study aimed to examine VCI prevalence and related risk factors in twin pregnancies and its association with adverse perinatal outcomes. Methods: Women with twin pregnancies who delivered between January 2012 and December 2021 in a single tertiary hospital were included. The participants were divided into dichorionic (DC) and monochorionic diamniotic (MCDA) groups, and their maternal and fetal characteristics and VCI rates were compared. Logistic regression models were used to identify risk factors for VCI and VCI-related perinatal outcomes. Results: Among the 694 twin pregnancies included in this study, the VCI rate was significantly higher in MCDA than in DC twins. Body mass index and MCDA twins were significant risk factors for VCI, whereas assisted reproductive technology pregnancy was a significant protective factor against VCI. In DC twins, VCI did not affect perinatal outcomes. Conclusion: In MCDA twins, VCI was a significant risk factor for fetal growth restriction, twin-to-twin transfusion syndrome, and preterm birth at
Vasa previa is a rare obstetrical complication with the high
risk of fetal death or demise if these are left unrecognized
before the rupturing of membranes. It is a condition in which
fetal blood vessels traverse the lower uterine segment in
advance of the presenting part. In this neither the umbilical
cord nor the placenta supports the vessels. Fetal mortality for
cases not recognized before the onset of labor is reported to
range between 22.5% and 100%.1,2 Vasa is a plural of vas
which comes from the latin word denoting the vessel or a
dish. Previa is a combination of two words. Pre means
before and via means the way. Previa in the medicine
usually refers to anything obstructing the passage in the
childbirth therefore the vasa previa means the vessels in the
way before the baby. Lobestein reported the first case of
rupture of vasa previa in 1801.3
The first ultrasound
description of vasa previa dates back to 1987
Introduction
During pregnancy, the umbilical cord attaches to the placenta in a central, eccentric, marginal or velamentous location. Maternal and fetal complications are associated with marginal and velamentous cord insertions, the most clinically significant being perinatal mortality due to undiagnosed vasa praevia. Current literature describes a wide variation regarding regulation of placental cord insertion (PCI) documentation during antenatal ultrasound examinations. This prospective cross‐sectional study aimed to assess the current practice of antenatal PCI documentation in Australia.
Methods
Members of the Australian Sonographer Accreditation Registry were invited to participate in an online survey which was distributed between February and March 2022.
Results
Four hundred ninety sonographers met the inclusion criteria for the study of which 330 (67.3%) have more than 10 years' experience as a sonographer and 375 (76.5%) are employed primarily in a public or private setting offering general ultrasound. Most respondents (89.6%) indicated documentation of the PCI site is departmental protocol at the second trimester anatomy scan (17–22 weeks gestation), but PCI documentation is protocol in less than 50% of other obstetric ultrasound examinations listed in the survey. The PCI site is included in the formal ultrasound report at a rate significantly less than inclusion in the departmental protocol and the sonographer's worksheet.
Conclusions
Considering the potential maternal and fetal complications associated with abnormal PCI and the ease at which the PCI site is identified in the first and second trimesters, we believe that standard inclusion of the PCI site in departmental protocol and in the formal ultrasound report from 11 weeks gestation, regardless of whether it is normal or abnormal, would prove invaluable.
Objective
To examine the relationship between umbilical cord insertion site, placental pathology and adverse pregnancy outcome in a cohort of normal and complicated pregnancies.
Methods
Sonographic measurement of the cord insertion and detailed placental pathology were performed in 309 participants. Associations between cord insertion site, placental pathology and adverse pregnancy outcome (pre‐eclampsia, preterm birth, small‐for‐gestational age) were examined.
Results
A total of 93 (30%) participants were identified by pathological examination to have a peripheral cord insertion site. Only 41 of the 93 (44%) peripheral cords were detected by prenatal ultrasound. Peripherally inserted cords were associated significantly ( P < 0.0001) with diagnostic placental pathology (most commonly with maternal vascular malperfusion (MVM)); of which 85% had an adverse pregnancy outcome. In cases of isolated peripheral cords, without placental pathology, the incidence of adverse outcome was not statistically different when compared to those with central cord insertion and no placental pathology (31% vs 18%; P = 0.3). A peripheral cord with an abnormal umbilical artery (UA) pulsatility index (PI) corresponded to an adverse outcome in 96% of cases compared to 29% when the UA‐PI was normal.
Conclusions
This study demonstrates that peripheral cord insertion is often part of the spectrum of findings of MVM disease and is associated with adverse pregnancy outcome. However, adverse outcome was uncommon when there was an isolated peripheral cord insertion and no placental pathology. Therefore, additional sonographic and biochemical features of MVM should be sought when a peripheral cord is observed. © 2023 International Society of Ultrasound in Obstetrics and Gynecology.
The placenta is the interface between mother and child, and has a decisive influence on the development of the unborn child and the health of the mother. All too often, no special attention is paid to the role of the placenta. However, it is placenta-related changes, variations in development or disease, and associated complications that represent some of the major causes of maternal and neonatal morbidity and mortality. Understanding etiology and pathophysiology, using proper diagnostic methods, and implementing targeted therapy can help reduce maternal mortality and improve neonatal outcome. The following chapter discusses the major topics of placenta-related hemorrhage such as the placenta accreta spectrum (PAS), placenta praevia, variations of umbilical cord insertion, premature placental abruption, and placental tumors.
Objective:
Despite its high prevalence and the possible link with perinatal complications, marginal cord insertion (MCI) is surrounded by considerable controversy regarding management. Our aim through this meta-analysis was to study its association with several perinatal outcomes in a manner that provides trustworthy and exact effect measures, enabling us eventually to evaluate its overall risk for pregnancy.
Data sources:
A systematic search was performed in Medline, Scopus, and the Cochrane Library as of 30th July 2022 to identify eligible studies.
Study eligibility criteria:
Observational studies including singleton pregnancies and comparing MCI to central/eccentric cord insertion (CCI), either prenatally or postnatally identified, were considered eligible.
Study appraisal and synthesis methods:
The Newcastle-Ottawa scale was used to assess study quality, and the QUIPS tool was used to assess bias risk. The main outcome was small for gestational age (SGA) neonates. Q test and an I2 score were used to assess study heterogeneity. The analyses were carried out using random-effects model, and the results were expressed as relative risk or mean difference with a 95% confidence interval.
Results:
In total, 15 studies (13 cohort studies and two case-control studies) contributed data to the analysis. In seven of these, there was a prenatal and in eight a postnatal diagnosis. The overall prevalence of MCI was 6.15% (1.13-11.3%). MCI pregnancies compared to CCI ones were found to be at higher risk of SGA neonates (RR: 1.25; 95% CI:1.21-1.29), preeclampsia (RR: 1.61; 95% CI:1.54-1.67), placental abruption (RR: 1.53; 95% CI:1.34-1.75), stillbirth (RR: 1.97; 95% CI:1.02-3.78), preterm delivery (RR: 1.47; 95% CI:1.24-1.75), lower mean gestational age at birth (MD: -0.20; 95% CI: -0.38 to -0.01), emergency cesarean delivery (RR: 1.39; 95% CI:1.35-1.44), lower mean birthweight (MD: -139.19; 95% CI: -185.78 to -92.61), 5-minute Apgar score <7 (RR: 1.48; 95% CI:1.00-2.19) and neonatal intensive care unit admission (RR: 1.57; 95% CI:1.20-2.06). When only prenatally diagnosed MCI pregnancies were considered, the risk remained high regarding SGA (RR: 1.34; 95% CI:1.21-1.48), preeclampsia (RR: 1.42; 95% CI:1.01-1.99), stillbirth (RR: 2.99; 95% CI:1.03-8.70), preterm delivery (RR: 1.41; 95% CI:1.19-1.68), lower mean gestational age at birth (MD: -0.22; 95% CI: -0.33 to -0.11) and lower mean birthweight (MD: -122.41; 95% CI: -166.10 to -78.73).
Conclusions:
Through this analysis the higher risk that MCI poses for pregnancy, regarding several adverse outcomes, became evident. Many of these associations persisted among the prenatally diagnosed pregnancies. The underlining pathophysiology should be investigated and further research is needed on the effect of increased surveillance in improving perinatal outcomes.
The objective of this exploratory modelling study was to estimate the effects of second-trimester, ultrasound-based antenatal detection strategies for vasa praevia (VP) in a hypothetical cohort of pregnant women. For this, a decision-analytic tree model was developed covering four discrete detection pathways/strategies: no screening; screening targeted at women undergoing in-vitro fertilisation (IVF); screening targeted at women with low-lying placentas (LLP); screening targeted at women with velamentous cord insertion (VCI) or a bilobed or succenturiate (BL/S) placenta. Main outcome measures were the number of referrals to transvaginal sonography (TVS), diagnosed and undiagnosed cases of VP, overdetected cases of VCI, and VP-associated perinatal mortality. The greatest number of referrals to TVS occurred in the LLP-based (2,083) and VCI-based screening (1,319) pathways. These two pathways also led to the highest proportions of pregnancies diagnosed with VP (VCI-based screening: 552 [78.9% of all pregnancies]; LLP-based: 371 [53.5%]) and the lowest proportions of VP leading to perinatal death (VCI-based screening: 100 [14.2%]; LLP-based: 196 [28.0%]). In contrast, the IVF-based pathway resulted in 66 TVS referrals, 50 VP diagnoses (7.1% of all VP pregnancies), and 368 (52.6%) VP-associated perinatal deaths which was comparable to the no screening pathway (380 [54.3%]). The VCI-based pathway resulted in the greatest detection of VCI (14,238 [99.1%]), followed by the IVF-based pathway (443 [3.1%]); no VCI detection occurred in the LLP-based or no screening pathways. In conclusion, the model results suggest that a targeted LLP-based approach could detect a substantial proportion of VP cases, while avoiding VCI overdetection and requiring minimal changes to current clinical practice. High-quality data is required to explore the clinical and cost-effectiveness of this and other detection strategies further. This is necessary to provide a robust basis for future discussion about routine screening for VP.
The rate of twin pregnancies has increased over the last decades, largely because of the ongoing development of assisted reproductive technology and increased maternal age at childbearing. Twins have a higher risk of adverse outcomes during pregnancy and the perinatal period. The prevalence of umbilical cord abnormalities is higher for twin pregnancies compared with singleton pregnancies. Some of these abnormalities are nonspecific to twinning and can also be found in singleton gestations (such as velamentous cord insertion, vasa previa, and single umbilical artery). Other abnormalities are associated with monochorionic twins, such as umbilical cord entanglement, and umbilical proximate cord insertion. Most of these abnormalities can be detected by ultrasound evaluation. The early and accurate ultrasound diagnosis of chorionicity, amnionicity, and placental and umbilical cord characteristics is crucial if we are to predict the risk of complications and to determine the best management for twin pregnancies. Histopathological examination of the placenta and umbilical cord after delivery can help to confirm prenatal diagnosis and to provide a better understanding of the physiopathology of their abnormalities. The aim of this review was to emphasize the role that the umbilical cord plays in twin complications and to describe the management of these high-risk pregnancies.
Introduction:
Twin pregnancies are classified into two groups: monochorionic (MC) and dichorionic (DC). MC twins are 5 to 6 times more likely to have an adverse perinatal outcome. The study of a group of 22 placentas from patients with monochorionic twin pregnancy who presented with complications such as feto-fetal transfusion syndrome (FFTS), twin anemia polycythemia sequence (TAPS), twin reverse arterial perfusion syndrome (TRAP) and selective intrauterine growth restriction (sIUGR) is presented.
Objective:
To determine the predominant types of anastomoses in placentas with feto-fetal transfusion syndrome, twin anemia polycythemia sequence, reverse arterial perfusion syndrome and selective intrauterine growth restriction. Methodology: The placental injection technique was applied for the recognition of anastomoses.
Results:
The mean number of anastomoses per placenta in STFF, which was the most severe complication, was 8.2 ± 2.2. The AV and VA anastomoses predominated in 83%. There were signs of placental discordance in 30% of placentas, and 40% of placentas presented velamentous cord insertion.
Conclusions:
Vascular anastomoses are not only involved in the etiology of the main pathologies of monochorionic gestations, but also influence their management. We believe that an adequate placental study of each of these cases by means of the placental vascular injection technique would be essential in centers that aspire to develop differentiated fetal management for each of these complications.
This authoritative textbook provides a much-needed guide for postgraduate trainees preparing for the European Board and College of Obstetrics and Gynaecology (EBCOG) Fellowship examination. Published in association with EBCOG, it fully addresses the competencies defined by the EBCOG curriculum and builds the clinical practice related to these competencies upon the basic science foundations. Volume 1 covers the depth and breadth of obstetrics, and draws on the specialist knowledge of four highly experienced Editors and over 100 contributors from across Europe, reflecting the high-quality training needed to ensure the safety and quality of healthcare for women and their babies. It incorporates key international guidelines throughout, along with colour diagrams and photographs for easy understanding. This is an invaluable resource, not only for postgraduate trainees planning to sit the EFOG examination, but also for practising specialists looking to update their knowledge and skills to meet the ever-evolving complexity of clinical practice.
Disclosure of incident on our successful outcome childbirth in term pregnancy velamentous insertion of the umbilical cord – vasa previa. Pregnant firstborn with free individuals and obstetrical history covering the 39th week of pregnancy is introduced in Maternity Clinic of our with symptomatology of automatic start birth. Sudden and to thoroughly grade vaginal hemorrhage found immediately after technical rupture of fetal membranes accompanied by decelerations of the fetal heartbeat raised the possible diagnosis of velamentous insertion of the umbilical cord – vasa previa and the interest undergone emergency cesarean section. After removal of the fetus and placenta was there synovial adherence cord. The caesarean section was performed smoothly with physiological loss blood. There was no need for blood transfusion in neonates, as well as it did not take neonatal support. Following a smooth postoperative course left together with the postpartum at fifth day of hospitalization. At this paper on the basis of current data a brief literature review of rare disease entities this respect mainly the diagnosis, treatment and prognosis.
Objective:
There is wide variation in the management of pregnancies complicated by abnormal placental cord insertion (PCI), which includes velamentous cord insertion (VCI) and marginal cord insertion (MCI). We tested the hypothesis that abnormal PCI is associated with small for gestational age (SGA) infants.
Study design:
This is a retrospective cohort study of all pregnant patients undergoing anatomic ultrasound at a single institution from 2010 to 2017. Patients with abnormal PCI were matched in a 1:2 ratio by race, parity, gestational age at the time of ultrasound, and obesity to patients with normal PCIs. The primary outcome was SGA at delivery. Secondary outcomes were cesarean delivery, preterm delivery, cesarean delivery for nonreassuring fetal status, 5-minute Apgar score < 7, umbilical artery pH < 7.1, and neonatal intensive care unit admission. These outcomes were compared using univariate and bivariate analyses.
Results:
Abnormal PCI was associated with an increased risk of SGA (relative risk [RR]: 2.43; 95% confidence interval [CI]: 1.26-4.69), increased risk of preterm delivery <37 weeks (RR: 3.60; 95% CI: 1.74-7.46), and <34 weeks (RR: 3.50; 95% CI: 1.05-11.63) compared with patients with normal PCI. There was no difference in rates of cesarean delivery, Apgar score of <7 at 5 minutes, acidemia, or neonatal intensive care unit admission between normal and abnormal PCI groups. In a stratified analysis, the association between abnormal PCI and SGA did not differ by the type of abnormal PCI (p for interaction = 0.46).
Conclusion:
Abnormal PCI is associated with an increased risk of SGA and preterm delivery. These results suggest that serial fetal growth assessments in this population may be warranted.
Key points:
· Abnormal PCI is associated with SGA infants and preterm birth.. · If an abnormal PCI is identified, the provider should consider serial growth ultrasounds.. · There is no difference in obstetric outcomes between VCI and MCI..
Objectives
Evaluate ultrasound diagnostic accuracy, maternal−fetal characteristics and outcomes in case of vasa previa diagnosed antenatally, postnatally or with spontaneous resolution before delivery.
Methods
Monocentric retrospective study enrolling women with antenatal or postnatal diagnosis of vasa previa at Sant’Anna Hospital in Turin from 2007 to 2018. Vasa previa were defined as fetal vessels that lay 2 cm within the uterine internal os using 2D and Color Doppler transvaginal ultrasound. Diagnosis was confirmed at delivery and on histopathological exam. Vasa previa with spontaneous resolutions were defined as fetal vessels that migrate >2 cm from uterine internal os during scheduled ultrasound follow-ups in pregnancy.
Results
We enrolled 29 patients (incidence of 0.03%). Ultrasound antenatally diagnosed 25 vasa previa (five had a spontaneous resolution) while four were diagnosed postnatally, with an overall sensitivity of 96.2%, specificity of 100%, positive predictive value of 96.2%, and negative predictive value of 100%. Early gestational age at diagnosis is significally associate with spontaneously resolution (p 0.023; aOR 1.63; 95% IC 1.18–2.89). Nearly 93% of our patient had a risk factor for vasa previa: placenta previa at second trimester or low-lying placenta, bilobated placenta, succenturiate cotyledon, velametous cord insertion or assisted reproduction technologies.
Conclusions
Maternal and fetal outcomes in case of vasa previa antenatally diagnosed are significally improved. Our data support the evaluation of umbilical cord insertion during routine second trimester ultrasound and a targeted screening for vasa previa in women with risk factor: it allows identification of fetus at high risk, reducing fetal mortality in otherwise healthy newborns.
We discuss practical points and useful tips which are helpful in evaluating patients for vasa previa. This article is protected by copyright. All rights reserved.
Objective:
To evaluate the association between antenatal diagnosis of velamentous and marginal placental cord insertions with adverse perinatal outcomes of small-for-gestational-age (SGA) birth weight (less than the 5th percentile), caesarean birth, and perinatal mortality.
Methods:
Using a diagnostic imaging database, we performed a cohort study of all consecutive singleton pregnancies (35,391), including 1,427 cases of marginal and 107 cases of velamentous cord insertion, delivered after 24 6/7 weeks of gestation between January 1, 2012, and December 31, 2015, at a single Canadian tertiary care center. Cases with placenta previa, vasa previa, no documented cord insertion, or fetal anomalies were excluded.
Results:
In the overall cohort, the rate of birth weight less than the 5th percentile was 5.2%, the rate of cesarean delivery was 27.1%, and the rate of perinatal mortality was 0.24%. Velamentous cord insertion was associated with SGA (relative risk [RR] 2.19, 95% CI 1.28-3.74). This persisted after controlling for smoking during pregnancy, diabetes, and hypertension (adjusted odds ratio [aOR] 1.98, 95% CI 1.03-3.84). Velamentous cord insertion was also associated with an increased risk of caesarean birth (RR=1.38, 95% CI=1.08-1,77) and perinatal death (1.87%, RR 8.15, 95% CI 2.02-32.8), a relationship that persisted after controlling for smoking during pregnancy, diabetes, and hypertension (aOR 1.53, 95% CI 1.01-2.32). Marginal cord insertion was not associated with birth weight less than the 5th percentile (RR 1.23, 95% CI 1.00-1.51), cesarean delivery (RR 1.01, 95% CI 0.92-1.10), or perinatal death (RR 1.53, 95% CI 0.62-3.78).
Conclusion:
Antenatal diagnosis of velamentous placental cord insertion is associated with birth weight less than the 5th percentile.
Velamentous and marginal umbilical cords are uncommon abnormalities of placental cord insertion that can entail significant fetal risk. We undertook this investigation to assess the ability of prenatal sonography to reveal abnormal insertions of the umbilical cord into the placenta.
Forty-six patients had both prenatal sonographic evaluation of the placental cord insertion site and postnatal pathologic examination. Distance from the insertion site to the nearest placental edge was categorized by sonography and pathology as normal if greater than 1 cm and abnormal if less than or equal to 1 cm. Sonographic and pathologic findings were compared.
Thirty-eight singleton and eight twin pregnancies, for a total of 54 cord insertions, were studied. Of the 43 sonographically normal insertions, 38 had normal pathologic findings, and the remaining five insertions had abnormal pathologic findings (all marginal cord insertions). All 11 insertions that showed abnormality on sonography were abnormal on pathologic examination (seven marginal and four velamentous insertions). Sonography was able to reveal a difference between the two types of abnormal insertions in only a single patient, in whom the cord insertion changed from marginal to velamentous during a 7-week interval. Sonography had an overall sensitivity of 69% (11/16), a specificity of 100% (38/38), and an accuracy of 91% (49/54) for revealing abnormal placental cord insertion sites.
Targeted sonographic examination of the placental site of umbilical cord insertion will reveal abnormal placental cord insertions, although distinguishing the specific type of abnormal insertion may require the use of color Doppler imaging.
Preface.- Examination of the placenta.- Macroscopic features of the delivered placenta.- Microscopic survey.- Placental types.- Early development of the human placenta.- Basic structure of the villous trees.- Architecture of normal villous trees.- Characterization of the developmental stages.- Nonvillous parts and trophoblast invasion.- Involution of implantation site - retained placenta.- Anatomy and pathology of the placental membranes.- Anatomy and pathology of the umbilical cord and major fetal vessels.- Placental shape aberrations.- Histopathologic approach to villous alterations.- Classification of villous maldevelopment.- Erythroblastosis fetalis and hydrops fetalis.- Transplacental hemorrhage, cell transfer, trauma.- Fetal storage disorders.- Maternal diseases complicating pregnancy - diabetes - tumors - pre-eclampsia - lupus anticoagulant.- Infectious diseases.- Abortion, Placentas of trisomies, and immunological considerations of recurrent reproductive failure.- Molar pregnancies.- Trophoblastic neoplams.- Benign tumors, chorangiosis.- Multiple pregnancies.- Legal considerations.- Glossary.- Normative values and tables.- Index.
Vasa previa is a rarely reported condition in which the fetal blood vessels, unsupported by either the umbilical cord or placental tissue, traverse the fetal membranes of the lower segment of the uterus below the presenting part.The condition has a high fetal mortality due to fetal exsanguination resulting from fetal vessels tearing when the membranes rupture. Despite improvements in medical technology, vasa previa often remains unsuspected until this fatal fetal vessel rupture occurs. Significant reduction in the fetal mortality from this condition depends on a high index of suspicion leading to antenatal diagnosis, and elective delivery by cesarean.We believe transvaginal ultrasound in combination with color Doppler is the most effective tool in the antenatal diagnosis of vasa previa and should be utilized in patients at risk, specifically those with bilobed, succenturiate-lobed, and low-lying placentas, pregnancies resulting from in vitro fertilization, and multiple pregnancy. Where there has been antepartum or intrapartum hemorrhage, especially when associated with fetal heart irregularities, we also recommend a test to exclude fetal blood in the vaginal blood. Similarly, amnioscopy before amniotomy may help to diagnose this condition. Cesarean delivery is the method of delivery of choice, and aggressive resuscitation of the affected neonate may be life saving. With a high index of suspicion, antenatal diagnosis using transvaginal sonography in combination with color Doppler, elective delivery by cesarean, and aggressive resuscitation of the neonate where fetal vessel rupture has occurred, the mortality from this complication may be considerably reduced. Target Audience: Obstetricians & Gynecologists, Family Physicians Learning Objectives: After completion of this article, the reader will be able to identify the risk factors and associated conditions for vasa previa, to identify the various clinical presentations and management of vasa previa, and to be aware of the diagnostic tools available to make the antepartum diagnosis of vasa previa.
In order to evaluate the clinical significance of velamentous cord insertion (VCI) and the role of ultrasound in its diagnosis, all 82 cases of VCI during January 1985 to January 1989 at the Mount Sinai Medical Center were reviewed. The overall rate of VCI in our study (0.5%) was similar to that of previous reports. Pregnancy outcomes in VCI patients with 77 singleton gestations were compared with a control group of 15,865 patients. In contrast to the existing literature, multiparity and prior cesarean section deliveries were not increased in pregnancies with VCI. The VCI group had more intrapartum complications and a lower birthweight than the controls. Routine nontargeted obstetric ultrasound failed to detect any cases of VCI, including three cases of vasa previa. Since VCI was not identified prenatally and many of its sequelae are readily identifiable only during the intrapartum period, the potential for preemptive obstetric intervention appears to be limited. In addition, failure to diagnose apparent VCI during a routine ultrasound does not appear to be a departure from the standard of care.
Previous studies have documented an increased incidence of structural defects in association with velamentous and marginal insertion of the umbilical cord. Evaluation of 4,677 consecutive placentas at the University of California (San Diego) Medical Center revealed 454 marginal insertions and 72 velamentous insertions. An increased incidence of structural defects was found only in association with a velamentous cord insertion. Delineation of the structural defects according to their developmental pathogenesis revealed that the majority were due to deformation of a normally formed part. These data and the finding of a disproportionate number of twins with a velamentous insertion suggest that competition for space at the implantation site leads to both the velamentous insertion of the cord and the associated structural defects.
Single umbilical artery (SUA) and velamentous insertion of the umbilical cord (VIU) were observed in 0.44 and 2.17%, respectively in a series of 14050 placentae which were systematically examined. The birth weights for both these groups were lower than for the reference material, with the lowest mean value in the SUA-group. The ponderal index, indicating insufficient intrauterine supply of nutrients, was relatively more reduced than the head circumference--especially in the SUA-group. Among twins where only one had VIU most of the VIU-twins showed a comparable lower birth weight than the other twin. The mean gestational age was only moderately reduced in both groups, though there was quite a high number of premature births. Both bilobate placenta and placental infarcts were registered somewhat more frequently in both groups than in the reference material while circumvallate placenta was found more frequently in the SUA-group only. None of the groups showed reduced placental weight when correlated with birth weight.
To evaluate the association between velamentous cord insertion and adverse pregnancy outcome in singleton pregnancies, and to assess the diagnostic usefulness of nonstress testing (NST) and Doppler ultrasound in this condition.
We retrospectively reviewed 12,750 consecutive singleton, chromosomally normal pregnancies from July 1989 through December 1993 at the University Hospital of Kuopio, Finland. Of these, 216 were complicated by velamentous umbilical cord insertion, whereas the remaining 12,534 were normal controls. Using multiple regression analysis, we evaluated the risks by noting adverse infant outcomes: low birth weight (LBW), small for gestational age (SGA), preterm delivery, fetal death, admission to a specific infant care unit, low Apgar scores, neonatal acidemia, and abnormal intrapartum fetal heart rate (FHR) patterns. At prenatal visits, NST and Doppler ultrasound examinations were carried out as a routine part of obstetric care.
Even after we controlled for confounding factors, velamentous umbilical cord insertion was associated with higher risk of LBW (odds ratio [OR] 2.32), SGA (OR 1.54), preterm delivery (OR 2.12), low Apgar scores at 1 and 5 minutes (ORs 1.76 and 2.47, respectively), and abnormal intrapartum FHR pattern (OR 1.59). Only 5% of the patients with abnormal insertion showed pathologic NST results at prenatal visits. Ultrasonographic examination was carried out on 80 patients with velamentous umbilical cord insertion as a routine part of obstetric care, and in only one case was direct visualization of the abnormal insertion successful. After we excluded pregnancies with preeclampsia, abnormal umbilical artery Doppler velocimetry was found in none of the cases examined (n = 48).
There were substantial differences in pregnancy outcome measures between the subjects with velamentous umbilical cord insertion and controls. Current antepartum methods of tracing uteroplacental problems are not effective in the prenatal detection of abnormal insertion. Therefore, in future studies, the use of other diagnostic tools, such as color Doppler imaging of cord insertion, should be evaluated in high-risk pregnancies followed-up because of fetal growth restriction.
Color Doppler and gray scale sonography can be used prenatally to identify the location of the cord insertion into the placenta. The purposes of this paper were to (1) relate sonographic identification of placental cord insertion with placental pathology; (2) evaluate the possibility that a marginal cord insertion may evolve into a velamentous cord insertion; and (3) determine the frequency and factors affecting sonographic visualization of cord insertion. Our results show that the sonographic assessment of cord insertion correlated with the pathologic outcome in 83% (106 of 128) of singleton pregnancies and at least one of the fetuses in 72% (8 of 11) of twin or triplet pregnancies. Although the sensitivity for identification of an abnormal cord insertion was low (42%), the specificity was high (95%). Our data suggest that marginal cord insertion evolved into velamentous cord insertion in one singleton and one twin. Our results showed that cord insertion was visualized in 54% of fetuses scanned in a routine clinical practice. Cord insertion visualization was possible at all gestational ages, although it was more difficult at later gestational ages. In conclusion, this study provides evidence that (1) ultrasonography (either gray scale or color Doppler) is useful in identifying normal, marginal, and velamentous cord insertion; (2) marginal cord insertion may evolve into velamentous cord insertion as pregnancy progresses; (3) in clinical practice the cord insertion site was visualized in just over half of the cases, and (4) prenatal identification of marginal and velamentous cord insertion potentially may be useful for planning obstetrical management.
To evaluate the umbilical cord and its abnormalities by use of three-dimensional ultrasonography with a specially developed abdominal three-dimensional transducer.
Ninety-five pregnancies (92 normal, 2 with hydrops fetalis, and 1 with omphalocele) from 14 to 40 weeks of gestation were studied with a specially developed abdominal three-dimensional transducer (3.5 MHz). This system can provide conventional two-dimensional ultrasonography images and can also generate within seconds high-quality three-dimensional images in the surface and transparent mode with no need for an external workstation. A proportion of the umbilical cords (coiled or noncoiled free loop, abdominal insertion, and placental insertion) visualized at each gestational age interval is presented.
The proportion of the umbilical cords visualized during pregnancy except for between 24 and 27 weeks of gestation was about 70% (range 64-83%). Optimal visualization of the umbilical cord was achieved between 24 and 27 weeks of gestation. During this period it was possible to adequately depict the umbilical cord in 93% of the cases. The proportions of the noncoiled umbilical cord depicted during pregnancy ranged from 8 to 45%. The detection rate of abdominal insertion of the umbilical cord visualized at 14-19 weeks was 44%; the detection rate decreased thereafter. Placental insertion of the umbilical cord could not be identified after 28 weeks of gestation. In 2 cases with hydrops fetalis, edematous umbilical cord was evident. In 1 fetus, omphalocele was clearly depicted.
The new three-dimensional ultrasound technology generates within seconds high-quality three-dimensional images of the umbilical cord, although limitation of viewing direction exists. These results suggest that the new three-dimensional ultrasonography has the potential to be a supplement to two-dimensional ultrasonography and might be useful in identifying abnormal umbilical cords in utero.
To determine whether cord insertion can be consistently visualized and whether velamentous cord insertion and vasa previa can be consistently identified with color Doppler imaging during routine sonography in the mid-trimester.
A prospective study.
A total of 587 fetuses at 18-20 weeks' gestation.
During routine ultrasound examinations, the sonographer was instructed to take additional time and to image the placental cord insertion with color Doppler imaging and classify this as normal, velamentous or 'not seen'. When the insertion was velamentous, the sonographer was instructed to indicate whether or not it was vasa previa. The sonogram obtained at 18-20 weeks' gestation was used for comparison with outcome data.
Cord insertion was visualized by color Doppler imaging in 99.8% (586/587) of the fetuses in our study. The mean time required for examination was 20 s and, in 95% of the cases, cord insertion was visualized within 1 min. The sonographic identification of velamentous cord insertion had a sensitivity of 100% (5/5), a specificity of 99.8% (580/581), a positive predictive value of 83% (5/6) and a negative predictive value of 100% (580/580). In our study, vasa previa was diagnosed at 18 gestational weeks in two cases and, in one of the cases, vasa previa was confirmed at delivery.
We could consistently identify cord insertion and velamentous cord insertion with color Doppler imaging during routine sonography in the mid-trimester. Transvaginal color Doppler imaging and serial scans were needed to identify vasa previa.
Unlabelled:
Vasa previa is a rarely reported condition in which the fetal blood vessels, unsupported by either the umbilical cord or placental tissue, traverse the fetal membranes of the lower segment of the uterus below the presenting part. The condition has a high fetal mortality due to fetal exsanguination resulting from fetal vessels tearing when the membranes rupture. Despite improvements in medical technology, vasa previa often remains unsuspected until this fatal fetal vessel rupture occurs. Significant reduction in the fetal mortality from this condition depends on a high index of suspicion leading to antenatal diagnosis, and elective delivery by cesarean. We believe transvaginal ultrasound in combination with color Doppler is the most effective tool in the antenatal diagnosis of vasa previa and should be utilized in patients at risk, specifically those with bilobed, succenturiate-lobed, and low-lying placentas, pregnancies resulting from in vitro fertilization, and multiple pregnancy. Where there has been antepartum or intrapartum hemorrhage, especially when associated with fetal heart irregularities, we also recommend a test to exclude fetal blood in the vaginal blood. Similarly, amnioscopy before amniotomy may help to diagnose this condition. Cesarean delivery is the method of delivery of choice, and aggressive resuscitation of the affected neonate may be life saving. With a high index of suspicion, antenatal diagnosis using transvaginal sonography in combination with color Doppler, elective delivery by cesarean, and aggressive resuscitation of the neonate where fetal vessel rupture has occurred, the mortality from this complication may be considerably reduced.
Target audience:
Obstetricians & Gynecologists, Family Physicians.
Learning objectives:
After completion of this article, the reader will be able to identify the risk factors and associated conditions for vasa previa, to identify the various clinical presentations and management of vasa previa, and to be aware of the diagnostic tools available to make the antepartum diagnosis of vasa previa.
To describe three-dimensional (3D) ultrasonography (US) for the antepartum diagnosis of vasa previa.
This was a descriptive study of two pregnant women who were suspected to have vasa previa by conventional gray-scale ultrasonography. Three-dimensional studies were also performed during the early third trimester to further investigate the possibility of this condition.
In the first case, 3D US provided gray-scale multiplanar and surface-rendered views of an aberrant vessel over the internal cervical os. For the second case, a 'flight-path' technique allowed the examiner to follow axial views of the endocervical canal toward the internal os until an aberrant vessel was verified. The 'niche-mode' analysis, with and without color power Doppler ultrasonography, was also used to confirm the diagnosis.
Three-dimensional ultrasonography offers several additional imaging tools that are not currently provided by more conventional ultrasonography for the detection of vasa previa. It represents an important adjunct to two-dimensional (2D) studies, especially when this diagnosis is questionable.
The placenta, umbilical cord, and membranes
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Diagnostic Imaging of Fetal Anomalies
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The placenta, umbilical cord, and membranes Lippincott Williams &
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Three-dimensional ultrasonographic assessment of the umbilical cord during the 2nd and 3rd trimesters of pregnancy
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