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A linear regression curve in triplet pregnancies with spontaneous onset of labour (group 2, n = 21) displaying the cervical length (CX, cm) and the time-to-delivery (weeks) from the first assessment (with 90% confidence limits for individual gestations).
Source publication
The current study aimed to evaluate the contribution of transvaginal sonography (TVS) for monitoring cervical changes during
the second half of triplet gestation. Forty-five pregnant women with triplets pregnancies were prospectively scanned by TVS
from ~26 weeks gestation and were longitudinally followed-up until delivery. Based on a receiver-oper...
Context in source publication
Context 1
... twins at 28 weeks gestation a cervical length of 25 mm had a 100% sensitivity for predicting Week of delivery 27.4 1.6CX 1 preterm delivery ). However, less promising results were reported for twins assessed at 18-26 weeks Based on a linear regression curve (Figure 3) we hereby present a mathematical equation for expressing the relation gestation in which a cervical length of 30 mm was found. ...
Similar publications
Introduction: The majority of pregnant women with a short cervix will deliver at term and, thus, may unnecessarily receive advanced monitoring and
treatment. It is still necessary to define more accurately which sub-population of women with a short cervix is at elevated risk for early delivery. Objective:
To determine if vaginal microbiome composit...
To examine the predictive value of cervical length as measured by transvaginal sonography (TVS) in supine and upright maternal positions for the mode of delivery and induction-to-delivery interval after induction of labor at term, and to compare these measurements with the Bishop score and its predictive value.
TVS for cervical length measurement i...
Objective To analyze the use of the measurement of uterine cervix length (MUCL) and the fetal fibronectin (fFN) rapid test as predictors of preterm delivery (PTD) in symptomatic pregnant women assisted at the Santa Casa de Misericórdia de Sobral Maternity Hospital.
Methods This was a prospective and analytic study involving 53 parturients assisted...
Objective:
The fetal fibronectin test is advocated to facilitate the management of women presenting with threatened preterm labour, but is underutilised in Hong Kong. This study aimed to provide experience with this test and evaluate its utility in a local setting.
Design:
Prospective cohort study.
Setting:
A university-affiliated hospital in...
Objective
To assess the impact of the introduction of universal transvaginal cervical screening and certification on the quality of cervical length ultrasound images.
Methods
The present study included a retrospective cohort of singleton pregnancies that underwent transvaginal cervical length measurement at the anatomical scan (180/7 and 236/7 wee...
Citations
... Cervical length can modify the a priori risk for preterm delivery. For example, a woman with a history of preterm delivery or one with a twin or triplet gestation will have a higher risk for preterm delivery than a patient with the same cervical length, but without such history (71)(72)(73)(74)(75)(76)(77)(78)(79)(80). It is now possible to provide women with an individualized estimation of risk for preterm delivery based upon cervical length and whether they have a history of preterm birth (81). ...
... Moreover, one could also hypothesize that chorionicity and/or the amount of amniotic fluid might influence cervical length (CL) in triplet pregnancies, probably even without having a major impact on gestational length. However, the efforts of identifying those women at risk for preterm triplet delivery have also focused on CL measurement [2,[8][9][10][11][12][13][14][15][16]. Despite the fact that these studies measured the CL at different pregnancy stages and resulted in different cut-off levels, they demonstrated that the CL can be used as a more or less reliable predictive tool. ...
... 0 weeks ( Table 2). The predictive value of CL on PTD has already been demonstrated in previous studies [2,4,8,9,[11][12][13][14][15][16]19]. Notably, optimized cut-off values for absolute CL were 34-35 mm in our study which resulted in sensitivity and specificity values of 60-80 and 70-90%, respectively. ...
... Notably, optimized cut-off values for absolute CL were 34-35 mm in our study which resulted in sensitivity and specificity values of 60-80 and 70-90%, respectively. Previous studies on triplet pregnancies often used a lower cut-off value of 25 mm [14,20] or calculated similar optimized cut-off values [11][12][13]. We find it hard to comment on these differences. ...
Purpose:
To review our experience with a screening program that included sequential cervical length measurements in our large population of triplet pregnancies.
Methods:
Seventy-eight triplet pregnancies were retrospectively included. Cervical length measurements were performed by transvaginal ultrasound in 2-week intervals from week 16 + 0 onwards in a tertiary-care center in Vienna. The main outcome measurement was preterm delivery prior to 32 + 0 weeks of gestation. Statistical analyses were performed using paired and unpaired t tests and a stepwise linear regression model.
Results:
There were 26 cases of preterm delivery (33.3%). Women with preterm delivery revealed significant cervical length shortening from week 22 + 0 (median 33 mm, interquartile range, IQR 17-39) to 24 + 0 (median 21 mm, IQR 7-30; p = 0.005). This was not observed in women without preterm delivery. From week 22 + 0 onwards, both groups showed further significant 2-week differences in cervical length (p < 0.05). Univariate analysis of cervical length in weeks 20 + 0, 22 + 0, and 24 + 0 as well as cervical length dynamics from 22 + 0 to 24 + 0 predicted preterm delivery.
Conclusions:
In triplet pregnancies, a decrease in cervical length seems physiological from week 22 + 0 onwards. A sharp decrease in cervical length from the 22 + 0 to the 24 + 0 week as well as the smaller cervical length in weeks 20 + 0, 22 + 0, and 24 + 0 increase the risk of preterm delivery.
... [9][10][11][12] However, data regarding the role of CL in triplet pregnancies and how the greater predisposition for PTB in triplet pregnancies, compared with twin pregnancies, is reflected by CL are limited. 5,[13][14][15][16][17] Specifically, it is unclear whether the greater predisposition of triplet pregnancies for PTB is reflected by a more rapid cervical shortening during gestation compared with twin pregnancies (and therefore a shorter CL at any given gestational age), by a greater risk for PTB per given CL at any given gestational age, or both. This information is of importance because it may assist clinicians in correctly interpreting CL at different points during gestation in women with triplet pregnancies. ...
... Data on the change in CL during gestation in triplet pregnancies are scarce. 15,16,19 Ramin et al 16 studied 32 women with triplet pregnancies and reported that CL (as measured by transperineal ultrasound scanning) at 10, 20, 25 and 30 weeks of gestation was 42, 37, 26, and 21 mm, respectively, which overall is similar to the mean CL that we observed in our study (20 weeks, 37 mm; 25 weeks, 31 mm; 30 weeks, 20 mm). The authors compared their finding with previously published data on longitudinal changes in CL in singleton pregnancies and concluded that CL in triplet pregnancies is significantly shorter, compared with singleton pregnancies, at any given gestational age. ...
... 23,24 Alternatively, the same factors that may be responsible for the more rapid cervical shortening in triplet pregnancies (eg, greater uterine overdistension) also may be more likely to trigger subclinical or overt uterine contractions in triplet pregnancies than in twin pregnancies, which would increase the risk of PTB in the presence of a given CL. Although there are data available on the accuracy of CL for the prediction PTB in triplet pregnancies, 5,6,[13][14][15][16][17][18]25,26 we were unable to identify studies that compared the accuracy of CL in triplet pregnancies with that observed in twin or singleton pregnancies. ...
... For example, in patients with a history of preterm delivery, a twin gestation, or a triplet gestation, a short cervix confers an increased risk for preterm delivery. 109,[141][142][143][144][145][146][147][148][149] Indeed, among women with a history of spontaneous preterm birth, the risk of recurrence increases as cervical length shortens. 9 ...
Recurrent preterm birth is frequently defined as two or more deliveries before 37 completed weeks of gestation. The recurrence rate varies as a function of the antecedent for preterm birth: spontaneous versus indicated. Spontaneous preterm birth is the result of either preterm labor with intact membranes or preterm prelabor rupture of the membranes. This article reviews the body of literature describing the risk of recurrence of spontaneous and indicated preterm birth. Also discussed are the factors which modify the risk for recurrent spontaneous preterm birth (a short sonographic cervical length and a positive cervicovaginal fetal fibronectin test). Patients with a history of an indicated preterm birth are at risk not only for recurrence of this subtype, but also for spontaneous preterm birth. Individuals of black origin have a higher rate of recurrent preterm birth.
... Cervical length can modify the a priori risk for preterm delivery. For example, a woman with a history of preterm delivery or one with a twin or triplet gestation will have a higher risk for preterm delivery than a patient without such history and the same cervical length [7,12,13, 22,27,40,41,44,47,49]. ...
A sonographically short cervix is a powerful predictor of spontaneous preterm delivery. However, the etiology and optimal management of a patient with a short cervix in the mid-trimester of pregnancy remain uncertain. Microbial invasion of the amniotic cavity (MIAC) and intra-amniotic inflammation are frequently present in patients with spontaneous preterm labor or acute cervical insufficiency. This study was conducted to determine the rate of MIAC and intra-amniotic inflammation in patients with a cervical length < 25 mm in the mid-trimester.
A retrospective cohort study was conducted of patients referred to our high risk clinic because of a sonographic short cervix or a history of a previous preterm birth. Amniocenteses were performed for the evaluation of MIAC and for karyotype analysis in patients with a short cervix. Fluid was cultured for aerobic and anaerobic bacteria, as well as genital mycoplasmas. Patients with MIAC were treated with antibiotics selected by their physician.
Of 152 patients with a short cervix at 14-24 weeks, 57 had amniotic fluid analysis. The prevalence of MIAC was 9% (5/57). Among these patients, the rate of preterm delivery (< 32 weeks) was 40% (2/5). Microorganisms isolated from amniotic fluid included Ureaplasma urealyticum (n=4) and Fusobacterium nucleatum (n=1). Patients with a positive culture for Ureaplasma urealyticum received intravenous Azithromycin. Three patients with Ureaplasma urealyticum had a sterile amniotic fluid culture after treatment, and subsequently delivered at term. The patient with Fusobacterium nucleatum developed clinical chorioamnionitis and was induced.
(1) Sub-clinical MIAC was detected in 9% of patients with a sonographically short cervix (< 25 mm); and (2) maternal parenteral treatment with antibiotics can eradicate MIAC caused by Ureaplasma urealyticum. This was associated with delivery at term in the three patients whose successful treatment was documented by microbiologic studies.
... [3][4][5][6][7][8] Transvaginal sonography for measuring cervical length has been proposed as a means for providing valuable information in the prenatal care of singleton, 9 twin, 10-14 and triplet gestations. [15][16][17][18] The objective of this study was to evaluate the role of sonographic assessment of cervical length before fetal reduction in predicting spontaneous preterm birth in triplet gestations reduced to twins. ...
... They found that a cervical length of 2.5 cm between 15 and 20 weeks' gestation had a sensitivity, specificity, PPV, and NPV of 25%, 100%, 100%, and 72%, respectively, for predicting spontaneous delivery before 32 weeks' gestation. To et al. 17 and Maymon et al. 18 evaluated cervical length in triplet pregnancies at 23 and of 26 weeks' gestation, respectively. ...
To evaluate the application of transvaginal sonography assessment of cervical length before fetal reduction for predicting spontaneous preterm birth in triplet gestations reduced to twins.
This retrospective study was conducted at the ultrasound unit of a university-affiliated municipal hospital. The study cohort consisted of 25 women with triplet gestations following ovulation induction or assisted-reproduction techniques who underwent fetal reduction to twins. Cervical length was assessed via transvaginal sonography before fetal reduction, and data on pregnancy outcome were retrieved from maternal records and/or maternal interviews.
Cervical length (mean +/- SD) at reduction was 4.0 +/- 0.85 (range: 1.2-5.5). Five women were excluded from statistical evaluation because pregnancy complications precluded spontaneous delivery. Two of 3 (67%) women with a cervical length of <3.5 cm delivered prior to 33 weeks' gestation compared with 1/17 (6%) women with a cervical length > or = 3.5 cm. This difference was statistically significant (P < 0.05). The sensitivity, specificity, positive predictive value, and negative predictive value of cervical lengths <3.5 cm to predict delivery prior to 33 gestational weeks was 67%, 94%, 67%, and 94%, respectively.
Measurement of cervical length in triplet pregnancies before fetal reduction provides useful predictive information on the risk for preterm delivery.
... All these women had multiple gestation. The use of transvaginal ultrasound assessment (TVS) during the pregnancy was proposed as first choice in any high-risk pregnancy for cervical incompetence (Maymon et al., 2001). Additionally, the preventive use of cervical cerclage and the bed rest was suggested to reduce the risk of preterm delivery in women at high risk for cervical incompetence such as women presenting cervical length , 2.5 cm before the 27th week of gestation during a transvaginal ultrasound assessment (Althuisius et al., 2002). ...
The difficulty of embryo transfer has been reported to affect success rates in some centres, but not in others. Cervical dilatation has been proposed as a means to overcome difficult embryo transfer, but consistent criteria for patient selection are lacking. In a prospective randomized study, we examined the influence of cervical dilatation 1-3 months before embryo transfer on the outcome of IVF in cases having difficult embryo transfer in two previously failed IVF cycles.
Two alternative methods of embryo transfer preparation were evaluated in 283 randomly assigned women having difficult embryo transfers in two previously failed IVF attempts. Randomization was made using a computer-generated random number table. Cervical dilatation before starting any IVF treatment was used in 145 cases, and no dilatation was performed in 138 cases.
The cervical dilatation group yielded a significantly higher pregnancy rate than the non-dilated group (40% versus 24%; P < 0.01). Likewise, the implantation rate (24.1% versus 14.9%; P < 0.01) and the live birth rate (34.48% versus 19.56%; P < 0.01) were significantly higher in the dilatation group than in the non-dilated group.
In patients with prior difficult embryo transfer, cervical dilatation 1-3 months before embryo transfer lead to an improved pregnancy rate.
... Cervical length less than 25 mm was demonstrated to have better predictive value at around 23 weeks gestation in other investigations (Goldenberg et al., 2000; Hassan et al., 2000). A 25 mm cervical length at 26 weeks gestation was found to be the best predictor of preterm birth at 33 weeks gestation in one study of triplet gestation (Maymon et al., 2001). ...
Objective:
To determine the sensitivity, specificity, and positive predictive value (PPV) of fetal fibronectin (fFN) and to determine its usefulness, in conjunction with selected other clinical assessment measures, in the prediction of preterm birth for women with twin gestations.
Design:
A prospective, descriptive, longitudinal design.
Setting:
An obstetrical high-risk clinic that received patient referrals from several surrounding communities in central Texas.
Patients/participants:
Forty-eight women identified with twin gestations prior to the 22nd week of pregnancy; primarily of Hispanic ethnicity.
Main outcome measures:
A substantial number of outcome variables were assessed in this study. In the present report, data derived from weekly assessments for the identification of the presence of fFN, the diagnosis of bacterial vaginosis, and the measurement of cervical length were reviewed for their relationship to prematurity, birth weight, birth weight discordancy and placental chorionicity.
Results:
The relative risk of birth prior to 35 weeks gestation, fetal death, or discordance of twin birth weights of greater than 20% was 2.22 (CI: 1.09, 4.55, P < 0.015) when fFN was found to be positive at any weekly testing after 22 to 24 weeks gestation (sensitivity 76.82%, specificity 58.33%, PPV 66.7%). The presence of fFN was most highly predictive of preterm birth when performed during the 24th to 28th gestational week. Shorter cervical lengths were highly correlated with preterm birth (r = -0.6). An association between bacterial vaginosis and preterm birth was not demonstrated in this sample.
Conclusion:
Sampling for the presence of fetal fibronectin can be easily accomplished by RNs in labor triage units and by advanced practice nurses in outpatient settings. The identification of fFN, particularly during the 24 to 28 weeks gestational time frame, is highly predictive of preterm birth, and particularly so for women with twin gestations.
... Our cervical assessment protocol was reported in depth elsewhere (Maymon et al., 2001). In brief, we aimed to obtain a sagittal view of the cervix and of the endocervical mucosa marking the cervical canal. ...
... Moreover, a single TVS examination at around 24 weeks of gestation was found to be sufficient for screening the patients at risk to deliver within the next 5 or 10 weeks in otherwise uncomplicated twin pregnancies. We contend that no additional information emerged from repeating the examination if the cervical length was ≥ 45 mm (Maymon et al., 2001). Contrary to Yang et al. (2000) we did not find a significant correlation between cervical funneling and cervical competence. ...
The present study aimed to determine a reliable tool to estimate the interval time to delivery in assisted conception twin pregnancies. Mid-gestation cervical length was prospectively measured using transvaginal sonography (TVS) during routine antenatal care. Fifty-seven of 101 suitable women were longitudinally followed and two TVS measurements of their cervical length were obtained, first at approximately 24 weeks gestation and then at approximately 27 weeks gestation. The mean cervical length decreased from 37 +/- 12mm at first measurement to 34 +/- 11mm at the second one. A linear regression model was found between the time interval of the first (R = 0.656, p < 0.001) and the second (R = 0.435, p < 0.001) assessments and the week of delivery. The current data confirm that the length of the preserved segment of the cervix is an important indicator of its competence. A simple equation using the cervical length (mm) divided by 3 can predict mid gestation scan-to-delivery interval in twin gestation.
... Our cervical assessment protocol was reported in depth elsewhere (Maymon et al., 2001). In brief, we aimed to obtain a sagittal view of the cervix and of the endocervical mucosa marking the cervical canal. ...
... Moreover, a single TVS examination at around 24 weeks of gestation was found to be sufficient for screening the patients at risk to deliver within the next 5 or 10 weeks in otherwise uncomplicated twin pregnancies. We contend that no additional information emerged from repeating the examination if the cervical length was ≥ 45 mm (Maymon et al., 2001). Contrary to Yang et al. (2000) we did not find a significant correlation between cervical funneling and cervical competence. ...
The present study aimed to determine a reliable tool to estimate the interval time to delivery in assisted conception twin pregnancies. Mid-gestation cervical length was prospectively measured using transvaginal sonography (TVS) during routine antenatal care. Fifty-seven of 101 suitable women were longitudinally followed and two TVS measurements of their cervical length were obtained, first at approximately 24 weeks gestation and then at approximately 27 weeks gestation. The mean cervical length decreased from 37 ± 12mm at first measurement to 34 ± 11mm at the second one. A linear regression model was found between the time interval of the first (R = 0.656, p < 0.001) and the second (R = 0.435, p < 0.001) assessments and the week of delivery. The current data confirm that the length of the preserved segment of the cervix is an important indicator of its competence. A simple equation using the cervical length (mm) divided by 3 can predict mid gestation scan-to-delivery interval in twin gestation.
