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Outcome of the cases that underwent first trimester screening, in National University Hospital and Singapore General Hospital, from 2006–2011.
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First trimester screening (FTS) is a validated screening tool that has been shown to achieve detection rates of 84%-90% for trisomies 21, 18 and 13. However, its effectiveness for different maternal ages has not been assessed. The present study aimed to assess the performance of FTS in an Asian population, and to compare its effectiveness in older...
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Context 1
... outcome of all cases that underwent FTS is summarised in Fig. 1. There was a total of 49 cases of trisomy (37 cases of trisomy 21, 11 cases of trisomy 18 and 1 case of trisomy 13), giving rise to a prevalence of 4.8 trisomies per 1,000 cases. The prevalence of trisomy 21 in the present study was 3.6 per 1,000 cases. When a risk cut-off value of 1:250 was applied, 293 of the 10,295 cases (2.85%) ...
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Background: A baby is said to be of low birth weight (LBW) if the estimated weight at birth is less than 2500g (5 pounds 8 ounces). LBW has serious and long lasting health implications for the baby, usually in the neonatal and infancy periods and may persist into adulthood. Several studies have been conducted in the past which looked into the relat...
Citations
... Before NIPT, serological screening for high-risk pregnant women was generally recommended for invasive prenatal diagnosis to determine the fetal chromosomal status. As the most sensitive screening method available, NIPT can effectively reduce the puncture rate (31,32), and many pregnant women with abnormal serological screening choose NIPT to avoid unnecessary invasive prenatal diagnoses (33). Karyotype analysis detects chromosomal aneuploidy abnormalities and obvious chromosomal structural abnormalities that can be observed under a microscope. ...
Although non-invasive prenatal testing (NIPT) is widely used to detect fetal abnormalities, the results of NIPT vary by population, and data for the screening efficiency of NIPT positive predictive value (PPV) from different populations is limited. Herein, we retrospectively analyzed the NIPT results in a large multicenter study involving 52,855 pregnant women. Depending on gestational age, amniotic fluid or umbilical cord blood was extracted for karyotype and/or chromosome microarray analysis (CMA) in NIPT-positive patients, and the PPV and follow-up data were evaluated to determine its clinical value. Among the 52,855 cases, 754 were NIPT-positive, with a positivity rate of 1.4%. Karyotype analysis and/or CMA confirmed 323 chromosomal abnormalities, with a PPV of 45.1%. PPV for trisomy 21 (T21), trisomy 18 (T18), trisomy 13 (T13), sex chromosomal aneuploidies (SCAs), and copy number variations (CNVs) were 78.9, 35.3, 22.2, 36.9, and 32.9%, respectively. The PPVs for T21, T18, and T13 increased with age, whereas the PPVs for SCAs and CNVs had little correlation with age. The PPV was significantly higher in patients with advanced age and abnormal ultrasound. The NIPT results are affected by population characteristics. NIPT had a high PPV for T21 and a low PPV for T13 and T18, and screening for SCAs and CNVs showed clinical significance in southern China.
... Therefore, trisomy 21 screening and diagnosis for the fetus is an important subject for pregnant women over 35 years old and other high-risk mothers. 2 First-trimester screening (FTS) is a valid screening method for major chromosomal aneuploidies. 3 FTS considers a combination of maternal age, Nuchal translucency (NT) Scan, and maternal serum. This maternal serum screening is done by a combination of two biochemical markers including serum free β-human chorionic gonadotrophin (free β-hCG) and pregnancy-associated plasma protein A (PAPP-A). 2 FTS is performed at 11 to 13 weeks of pregnancy; using ultrasound to scan the fetal neck for enlarged NT. ...
... The PPV of FTS in detecting trisomies 21, 18 and 13 at 1:1,000 selected risk cut-offs was 5.64%. 3 In another study that was performed in Iran by Heidari et al., predictive value of FTS markers for Down Syndrome (DS) in Iranian Pregnancies was evaluated. The PPV for PAPP-A, β-hCG, NT, and NB were 60.99%, 46.51%, 55%, and 100%, respectively. ...
Background: The aim of this study is to analyze the positive predictive value (PPV) of trisomies 21, 18 and 13 at first and second trimester using amniocentesis for clinical practice. Methods:This is a descriptive cross-sectional study in which data were extracted from a cohort project of mother and infant conducted between March 2016 and February 2021 among 3110 pregnant women in Yazd city. Results: Out of 3110 pregnant women, 84 mothers were at high risk in the screening tests of the first and second trimesters of pregnancy and therefore were candidates for amniocentesis. None of them were detected by the positive amniocentesis method. The mean age of mothers was 33.2 years. The causes of amniocentesis included old age (45.9%), positive results of Down syndrome screening (23%), high NT ultrasound (4.9%), and pathological results of anomaly scan sonography (3.8%). Conclusion: In this study, the PPV was zero and the number of false positives in screening tests was 84 (100%). This may be because our population was normal and had no history of genetic abnormalities or other special conditions.
... These parameters had individually proven significant relation in depicting certain adverse pregnancy outcomes (APOs) in the antenatal and perinatal period in many studies. [5][6][7][8] However, in our population, no study has reported such an effect so far, to the best of our knowledge; hence, this study was designed to check the effectiveness of this perspective retrospectively. ...
Context:
Aneuploidy screening is done in the early second trimester of pregnancy among all pregnant women as compulsory, with a special focus on those who had abnormal ultrasound parameters, higher dual marker risk, or other comorbidities. Recently, all individual quad markers of conventional trisomy screening have been suggested as useful in predicting adverse pregnancy outcomes (APO) such as preeclampsia, preterm labor, small for gestational age, and placental abruptions. However, similar studies on Indian pregnant women are limited. Hence, this study was intended to find the relation of quadruple markers with any other APO than aneuploidy.
Materials and methods:
A retrospective study was conducted in a Tertiary Care multi-specialty hospital in North India. Data from 252 pregnant women's quadruple test was analyzed. The association of abnormal value of quadruple markers (human chorionic gonadotropin [HCG]/alpha-fetoprotein/uE3/Inhibin A) with adverse outcomes was evaluated. Multiple logistic regression analysis and classification and regression tree were used to predict the significant risk factor in high-risk pregnancies.
Results:
In the study, a total (n = 252) of pregnant women, 190 were screened as high-risk pregnancies, whereas the remaining 62 were reported as low-risk using trisomy screening in the quadruple test. Baby birth weight was observed to be significantly associated with Inhibin-A, and HCG (P < 0.001), whereas Corrected (Corr)-multiple of median (MoM)-HCG (>1.415) and Inhibin-A Corr-MoM (>364.175) were the suitable predictor for the LBW. Both parameters were significantly higher in the high-risk group as compared to the low-risk group (each P < 0.05).
Conclusion:
Abnormal deviation of biochemical markers from aneuploidy screening assessment could help predict other perinatal adverse outcomes such as low birth weight babies.
... Therefore, it is very necessary to do a good job in the screening of fetal malformations and chromosomal abnormalities in the second trimester of pregnancy for older pregnant women. It can accurately screen fetal malformations, which is of great significance for the prediction of adverse pregnancy [3]. At present, the gold standard to screen fetal chromosomal abnormalities in clinical practice is invasive prenatal diagnosis, that is, amniocentesis diagnosis [4]. ...
Introduction:
To explore the clinical value of noninvasive prenatal testing (NIPT) in screening the chromosomal abnormalities of the fetus in the elderly pregnant women.
Materials and methods:
Between January 2020 and December 2021, 1949 elderly pregnant women underwent NIPT in our hospital. At the same time, 236 elderly pregnant women received invasive prenatal diagnosis, and the pregnancy outcomes were followed-up.
Results:
When NIPT was used for prenatal screening of fetal chromosomal aneuploidy, its diagnostic coincidence rate for trisomy 21 was the highest, with a coincidence rate of 90.00%, and the diagnostic coincidence rate for other chromosomal abnormalities was the lowest, only 22.22%. The sensitivity, specificity, positive predictive rate, and negative predictive rate for T21 by NIPT were 100%, 99.97%, 94.28%, and 100%; for T18 were 100%, 99.92%, 72.22%, and 100%, respectively; and for T13 were 100%, 99.95%, 50%, and 100%, respectively. Patients with high risks according to NIPT results further received invasive prenatal diagnosis, and 18 cases were excluded from the follow-up. For the remaining 1933 cases in the NIPT group, there was an incidence of 2.28% of adverse pregnancy outcomes. For the remaining 234 cases in the Amniocentesis group, there was an incidence of 1.28% of adverse pregnancy outcomes. There was no significant difference between the two groups (P > 0.05). The diagnostic rate of fetal chromosomal abnormalities in pregnant women under 40 years old was about 0.39-0.79%; however, the risk for people over 40 is relatively high at 1.32-4.44%.
Conclusion:
The noninvasive prenatal screening of fetal DNA in the second trimester of pregnancy for elderly pregnant women has high application value in the prediction of pregnancy outcome. The high risk of pregnancy can be determined by detecting trisomy 21, 18, and 13 syndromes, and the probability of adverse pregnancy outcome increases.
... As the most sensitive screening method, NIPT can effectively reduce the puncture rate in these pregnant women. 31,32 As a result, many pregnant women with abnormal serological screening are choosing NIPT to avoid unnecessary invasive prenatal diagnoses. 33 Karyotype analysis can detect all chromosomal aneuploidy abnormalities and obvious chromosomal structural abnormalities that can be seen under the microscope. ...
Non-invasive prenatal testing (NIPT) is a fast, safe, and non-disruptive diagnostic method. At present, few studies have evaluated the screening efficiency of NIPT positive predictive value (PPV) in study subjects. Here, the results of NIPT in pregnant women were retrospectively analysed, and the detection rate, PPV and follow-up data were evaluated to determine its clinical value. A large multicentre study was conducted involving 52,855 pregnant women who received NIPT. Based on gestational age, amniotic fluid or umbilical cord blood were extracted for simultaneous karyotype and chromosome microarray analysis (CMA) in NIPT-positive patients. Among the 52,855 cases, 754 were NIPT-positive, with a positivity rate of 1.4%. Karyotype analysis and/or CMA confirmed 323 cases of chromosomal abnormalities, with a PPV of 45.1%. PPV of Trisomy 21 (T21), Trisomy 18 (T18), Trisomy 13 (T13), sex chromosomal aneuploidies (SCA) and copy number variations (CNV) were 78.9%, 35.3%, 22.2%, 36.9% and 32.9%, respectively. The PPV of T21, T18, and T13 increased with age whereas, the PPV of SCA and CNVs had little correlation with age. The PPV was significantly high in patients with advanced age along with an abnormal ultrasound.
NIPT had a high PPV for T21, and a low PPV for T13 and T18, while screening for SCA and CNVs showed clinical significance. However, in case of NIPT screening for SCA and CNVs, simultaneous karyotype and CMA should be performed to increase the detection rates. Interventional prenatal diagnosis is still required in NIPT-positive cases to avoid false positives or unnecessary termination of pregnancy.
... Ayrıca bazı çalışmalarda orta risk olarak 1/100-1/2500 ve hatta 1/30-1/900 gibi farklı aralıklar kabul edilmiştir (7). Genel olarak, orta risk saptanan fetüsler için öncelikle maternal kanda fetal DNA tarama testi (noninvaziv prenatal tarama) önerilmekle beraber uygun danışmanlık sonrasında invaziv tanı seçeneği de sunulmaktadır (8). ...
İlk trimester tarama testi risk kategorilerinin gebelik sonuçları ile ilişkisi Özet Amaç: İlk trimester tarama testinde nukal saydamlık (NT) artışının, fetal anomali varlığının ve kombine testte risk artışının genetik hastalıklarla ilişkisi bilinmektedir. Ancak, kombine testte 1/250-1/2000 olarak belirlenen orta riskli grubun yönetimi tartışma konusudur. NT artışının, fetal anomali varlığının ve kombine testte yüksek ve orta risk gruplarının gebelik sonuçlarına dair veriye ihtiyaç duyulmaktadır. Buna dayanarak mevcut araştırmada, ilk trimesterde patolojik bulgu saptanan fetüslerin gebelik sonuçlarının değerlendirilerek, takip ve tedaviye yönelik sonuçlara varılması amaçlanmıştır. Gereç-yöntem: Yirmi aylık dönemde ilk trimester tarama testi ve ikinci trimester ayrıntılı fetal muayenesi tek bir perinatoloji ünitesinde tamamlanmış ve gebelik sonucu dökümante edilmiş 268 gebe çalışmaya dahil edildi ve fetal anomali varlığı, NT artışı (3.5 mm ve üzeri) ve kombine testte risk artışı olarak gruplara ayrıldı. Yüksek risk, kombine test riski 1/250 üzerinde ve/veya NT 3.5 mm üzerinde olması; orta risk ise kombine test riski 1/250-1/2000 arasında saptanması olarak kabul edildi. İnvaziv test uygulanan gebeliklerin fetal genetik sonuçlarına, spontan veya indüklenmiş terminasyonların ise fetal otopsi ve genetik sonuçlarına ulaşıldı. Veriler frekans (n) ve yüzde (%) olarak değerlendirildi. İlk trimester tarama testi için pozitif prediktif değer (PPD) hesaplamaları yapıldı. Bulgular: Çalışmaya alınan 268 tekil gebeliğin 46’sında (%17) sonografide anomali (n=18, %39) veya kombine test tarama sonucunda >1/2000 risk artışı (n=28, %61) saptandı. Merkezi sinir sistemi anomalileri en sık saptanan anomaliydi (9/18, %50). Anöploidi oranı en yüksek (%57) patoloji hidrops fetalis idi. Trizomi 21 saptanan fetüslerin %50’sinde (2/4) sonografik taramalar normaldi. Kombine testte yüksek ve orta riskin pozitif prediktif değeri sırası ile %29.4 ve %12.5 olarak hesaplandı. Sonuç: Trizomi 21 olgularının en az yarısında sonografik bulgu olmayabileceğinden, ultrason ve serum parametreleri kombine olarak ele alınmalıdır. Kombine testte orta riskli her 8 fetüsün birinde genetik anomali saptanabileceğinden, bu gruptaki gebeler için ileri tanı ve takip seçenekleri dikkatli şekilde planlanmalıdır.
... Some researchers suggested that the introduction of NIPS as a second line screening test, conditional to a risk ≥1:1000 from Standard of Care screening, showed a 3% increase in the detection of trisomies, with a 71% decrease in the number of invasive tests performed 23 . Other previous study suggest that the use of risk scores between 1:251 and 1:1000 may be a more cost-effective threshold 24 . While international experience provides some insights, it is very difficult to forecast how the availability and accessibility of NIPS will affect screening for fetal Down syndrome in China, particularly across models with varied definitions of high and intermediate risk. ...
To discuss combinations of traditional screening and noninvasive prenatal screening (NIPS) and to compare which traditional screening is the most suitable first-line screening approach to NIPS, pregnant women were recruited in this retrospective observational study. Pregnant women underwent one of four traditional screening tests. The 9 contingent models were combined by high risk cut-offs of 1:50, 1:100, 1:270 and intermediate risk cut-offs of 1:1000, 1:1500, 1:2000. We analyzed cost and performance of various screening models with contingent screening of different risk cut-offs. Compared with other screening tests, combined first-trimester screening (CFTS) had the lowest proportion of high risk (≥1:270) with the highest detection rate (DR) (78.79%) and the lowest proportion of intermediate risk (1:271~1:1000). When intermediate risk was 1:51 ~1:1500, CFTS as first-line screening had the lowest cost with DR of 93.94%. Other screening tests as the first-line screening with intermediate risk of 1:51~1:1000 had the lowest cost, there DR were 90.91%, 84.62%, 91.67%, respectively. Our study demonstrated if only one traditional screening was allowed to screen pregnant women, CFTS was recommended as the first choice. According to local health and economic conditions, adopting appropriate traditional screening with suitable cut-offs as first-line screening will contributed to a cost-effective screening model.
... maternal age in an Asian cohort " by Sarah WeilingLi et al, specifically, for pregnant women over 35 years old, the sensitivity and specificity of FTS were 85.71% (95% CI: 63.63% -96.78%) and 94.57% (95% CI: 93.64% -95.4%), respectively(Li et al., 2015). The effectiveness of FTS used in this study was similar to the cost-effectivestudy of NIPT and FTS by Stephen Morris et al done in the UK in 2013, Ken Song et al conducted in 2013 in the United States and Okun's study done in Canada (85% sensitivity) (S. ...
Background: Non-invasive prenatal testing (NIPT) is a relatively new technology for diagnosis of fetal aneuploidies in the context of a developing country like Vietnam. Currently, first-trimester screening (FTS) is more conventional in Vietnam. NIPT is assumed to be more accurate than other maternal screening but is also more costly. The purpose of the study was to perform a cost-utility analysis comparing the FTS and NIPT for Down syndrome for high-risk pregnant women (over 35-year-old) in Vietnam.
Methods: Decision tree model and probabilistic sensitivity analysis were used.
Results: With the modelling population of 27,232 over 35 years of age pregnant women, FTS helps detect 218.5 cases of the fetus with Down syndrome compared with 247.2 cases when screening with NIPT. In addition, NIPT reduced 1384 false-positive cases compared to FTS. From a societal perspective, NIPT-dominated FTS. Compared to FTS, adopting an NIPT would cost an additional of USD 3,800 for each additional quality-adjusted life-year gained.
Conclusions: NIPT is a cost-effective alternative to FTS for prenatal screening for Down syndrome with high-risk pregnant women. This is a very first attempt on cost-utility analysis of prenatal screening methods for Down syndrome in Vietnam and recommendations are made for future research to determine the most cost-effectiveness methods.
... 5-15 However, it may vary between differ- ent ethnicities as well as by age group. [16][17][18] According to the Fetal Medicine Foundation (FMF) pro- posed screening, patients with a risk lower than 1:1,000 are classified as low risk and are reassured. If we include the additional ultrasound marker of the presence of nasal bone and Doppler of the venous duct, the cut-off point for high- risk patients will be 1:100. ...
Objective The main objective of this study was to examine the diagnostic performance of the first-trimester combined test for aneuploidies in unselected pregnancies from Rio de Janeiro and compare it with the examples available in the literature.
Methods We investigated 3,639 patients submitted to aneuploidy screening from February 2009 to September 2015. The examination is composed of the Fetal Medicine Foundation risk evaluation based on nuchal translucency evaluation, mother's age, presence of risk factors, presence of the nasal bone and Doppler of the ductus venous in addition to biochemical analysis of pregnancy-associated plasma protein A (PAPP-A) and beta-human chorionic gonadotropin (β−hCG) markers. The cut-off point for high risk for aneuploidies was defined as greater than 1:100, with intermediate risk defined between 1:100 and 1:1,000, and low risk defined as less than 1:1,000. The variable aneuploidy was considered as a result not only of trisomy of chromosome 21 but also trisomy of chromosomes 13 and 18.
Results Excluding the losses, the results of 2,748 patients were analyzed. The first-trimester combined test achieved 71.4% sensitivity with a 7.4% false-positive (FP) rate, specificity of 92.6%, positive predictive value (PPV) of 6.91% and negative predictive value (NPV) of 99.76%, when the cut-off point considered was greater than 1:1,000. Through a receiving operating characteristics (ROC) curve, the cut-off point that maximized the sensitivity and specificity for the diagnosis of aneuploidies was defined as 1:1,860. When we adjusted the false-positive (FP) rate to 5%, the detection rate for this analysis is 72.7%, with a cut-off point of 1:610.
Conclusion The combined test of aneuploidy screening showed a detection rate inferior to those described in the literature for a higher FP rate.
... Our research demonstrated significantly lower PAPP-A levels in patients with high (> 1:50) risk of chromosomal aberrations as compared to controls, which is in line with previous research [22]. We did not analyse the correlation of ß-HCG level and the risk of chromosomal abnormalities in the two groups due to its established elevation in trisomy 21, and decrease in trisomy 13 and trisomy 18. ...
The primary objective in modern obstetrics and prenatal diagnosis is to predict risks of congenital abnormalities. The aim of the research was to assess the correlation between selected oxidative stress biomarkers with the risk of foetal chromosomal aberration evaluated at the first trimester screening. A series of studies show that balanced free radical activity and oxidative homeostasis are essential for proper bodily growth and function. Reactive oxygen species (ROS) may be one of the factors associated with disruption of cell cycle and tissue development, thus leading to developmental abnormalities. That's why it's so important to examine connection between level of oxidative stress and congenital abnormalities. Using ultrasonography examinations between 11-13+6d gestational weeks combined with serum levels of pregnancy associated plasma protein A and human chorionic gonadotropin and spectrophotometric analysis of oxidative stress markers such as glutathione (GSH), S-transferase, S-nitrosothiols (RSNO), trolox equivalent antioxidant capacity (TEAC), protein and nitrites we tried to find correlation between birth defects and oxidative stress status. In conclusion, our analysis suggests that elevated maternal serum levels of protein, S-transferase and TEAC as well as decreased maternal serum levels of GSH and protein correlated with the risk of chromosomal aberrations and congenital developmental defects in a foetus.
