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Objectives: Our aim was to examine the prenatal profiles of pregnancies affected by an atypical chromosomal aberration, focusing on pathogenic copy‐number variants (pCNVs). We also wanted to quantify the performance of combined first‐trimester screening (cFTS) and a second‐trimester anomaly scan in detecting these aberrations. Finally, we aimed to estimate the consequences of a policy of using non‐invasive prenatal testing (NIPT) rather than invasive testing with chromosomal microarray analysis (CMA) to manage pregnancies identified as high risk by cFTS. Methods: This was a retrospective review of the Danish Fetal Medicine Database of all pregnant women who underwent cFTS and a risk assessment for trisomy 21 between 1 January 2008 and 31 December 2018. Chromosomal aberrations diagnosed prenatally, postnatally or from fetal tissue following pregnancy loss or termination of pregnancy were identified. Chromosomal aberrations were grouped into one of six categories: triploidy; common trisomy (13, 18 or 21); monosomy X; other sex‐chromosome aberration (SCA); pCNV; and rare autosomal trisomy (RAT) or mosaicism. The prevalence of each aberration category was stratified by the individual cFTS markers and trisomy 21 risk estimate, and the size of each pCNV diagnosed by CMA was calculated. Results: We retrieved data on 565 708 pregnancies, of which 3982 (0.70%) were diagnosed with a fetal chromosomal aberration. cFTS identified 87% of the common trisomies, but it also performed well in identifying triploidies (86%), monosomy X (92%), atypical SCAs (58%) and RATs or mosaicisms (70%). pCNVs comprised 27% (n = 1091) of the chromosomal aberrations diagnosed overall, and the prevalence increased during the study period, as prenatal CMA was increasingly being performed. In pregnancies with a maternal age < 30 years, nuchal translucency (NT) thickness ≤ 95th centile, pregnancy‐associated plasma protein‐A (PAPP‐A) ≥ 1 multiple of the median, or trisomy 21 risk of ≤ 1 in 1000, the prevalence of pCNVs exceeded significantly the prevalence of trisomies 21, 18 and 13. Pregnancies affected by a pCNV had significantly increased NT and decreased levels of the maternal biomarkers PAPP‐A and β‐human chorionic gonadotropin compared with unaffected pregnancies. However, only 23% of these pregnancies screened positive on cFTS and 51% of pCNVs were not detected until after birth. Among high‐risk pregnancies, pCNVs comprised 14% of diagnosed aberrations, and when other atypical aberrations were considered, conventional NIPT (screening for trisomies 21, 18 and 13 and monosomy X) would miss 27% of all pathogenic aberrations diagnosed from invasive testing following a high‐risk cFTS result. Thus, 1 in 26 pregnancies at high risk following cFTS would be affected by a chromosomal aberration despite a normal result from conventional NIPT. In a contingent screening model using NIPT for the 'intermediate'‐risk group (trisomy 21 risk of 1 in 100–299), 50% of the aberrations would be missed. In our cohort, 79% of the pCNVs diagnosed were < 5Mb and therefore not detectable using current forms of 'genome‐wide' NIPT. Conclusions: As a by‐product of screening for trisomies 21, 18 and 13, most triploidies and the majority of atypical SCAs, RATs and mosaicisms are detected before birth. However, only 23% of pCNVs are associated with a high‐risk result according to cFTS and only half are diagnosed before birth. Replacing invasive testing with NIPT for high‐risk pregnancies would substantially decrease the first‐trimester detection of pathogenic chromosomal anomalies. © 2024 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology. [ABSTRACT FROM AUTHOR]

This article discusses the identification of partial hydatidiform mole (PHM) using non-invasive single-cell sequencing of fetal circulating extravillous trophoblasts (cEVTs) isolated from maternal blood. PHM is a condition that is typically triploid and associated with risks such as pre-eclampsia and gestational trophoblastic disease. The article presents a case study where a novel cell-based non-invasive prenatal testing (CB-NIPT) platform was used to accurately diagnose PHM. The study found that the number of cEVTs recovered from maternal blood was significantly higher in the PHM case compared to healthy controls, suggesting the potential for cEVTs as an early marker for associated hypertensive disorders and pre-eclampsia. Early diagnosis of PHM is crucial for optimal management and this study demonstrates the potential of CB-NIPT technology for early blood-based detection of PHM. [Extracted from the article]

Objectives: To examine the distribution of nuchal translucency thickness (NT), free β‐human chorionic gonadotropin (β‐hCG) and pregnancy‐associated plasma protein‐A (PAPP‐A) in pregnancies with a fetal 22q11.2 aberration. Furthermore, the performance of combined first‐trimester screening (cFTS) and a new risk algorithm targeting 22q11.2 deletions in detecting affected pregnancies was evaluated. Finally, prenatal malformations and pregnancy outcome were assessed. Methods: This was a nationwide registry‐based cohort study of all pregnancies that underwent prenatal screening with a due date between January 2008 and December 2018 in Denmark. All cases with a fetal 22q11.2 deletion or duplication (hg19 chr22:18.9mio‐25.0mio) diagnosed pre‐ or postnatally or following pregnancy loss or termination of pregnancy were retrieved from the Danish Cytogenetic Central Register and linked with pregnancy data from the Danish Fetal Medicine Database. Fetal and maternal characteristics, including cFTS results and pregnancy outcome, of pregnancies with any 22q11.2 deletion or duplication (LCR22‐A to ‐H) and pregnancies with a classic deletion or duplication (LCR22‐A to ‐D) diagnosed by chromosomal microarray were compared with those of a chromosomally normal reference group. A risk algorithm was developed for assessing patient‐specific risks for classic 22q11.2 deletions based on NT, PAPP‐A and β‐hCG. Detection rates and false‐positive rates at different risk cut‐offs were calculated. Results: We included data on 143 pregnancies with a fetal 22q11.2 aberration, of which 97 were deletions (54 classic) and 46 were duplications (32 classic). NT was significantly increased in fetuses with a classic deletion (mean, 1.89 mm), those with any deletion (mean, 1.78 mm) and those with any duplication (mean, 1.86 mm) compared to the reference group (mean, 1.65 mm). β‐hCG multiples of the median (MoM) was decreased in all 22q11.2 subgroups compared with the reference group (mean, 1.02) and reached significance in pregnancies with a classic deletion and those with any deletion (mean, 0.77 and 0.71, respectively). PAPP‐A MoM was significantly decreased in pregnancies with a classic duplication and those with any duplication (mean, 0.57 and 0.63, respectively), and was significantly increased in pregnancies with a classic deletion and those with any deletion (mean, 1.34 and 1.16, respectively), compared to reference pregnancies (mean, 1.01). The screen‐positive rate by cFTS was significantly increased in pregnancies with a classic deletion (13.7%), any deletion (12.5%), a classic duplication (46.9%) or any duplication (37.8%) compared to the reference group (4.5%). A risk algorithm targeting classic 22q11.2 deletions more than doubled the prenatal detection rate of classic 22q11.2 deletions, but with a substantial increase in the false‐positive rate. Structural malformations were detected in 41%, 35%, 17% and 25% of the pregnancies with a classic deletion, any deletion, classic duplication or any duplication, respectively. Pregnancy loss occurred in 40% of pregnancies with a classic deletion and 5% of those with a classic duplication diagnosed prenatally or following pregnancy loss. Conclusions: The distribution of cFTS markers in pregnancies with a classic 22q11.2 duplication resembles that of the common trisomies, with decreased levels of PAPP‐A. However, classic 22q11.2 deletions are associated with increased levels of PAPP‐A, which likely limits early prenatal detection using the current cFTS risk algorithm. The scope for improving early detection of classic 22q11.2 deletions using targeted risk algorithms based on NT, PAPP‐A and β‐hCG is limited. This demonstrates the capability, but also the limitations, of cFTS markers in detecting atypical chromosomal anomalies, which is important knowledge when designing new prenatal screening programs. © 2023 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology. [ABSTRACT FROM AUTHOR]

The article discusses the importance of prenatal screening in Denmark, focusing on detecting chromosomal aberrations and malformations beyond common trisomies. The Danish system emphasizes close monitoring during pregnancy to prepare parents and healthcare professionals for potential disabilities or serious medical conditions in the child. While current non-invasive prenatal testing (NIPT) methods may not effectively diagnose severe chromosomal anomalies, ongoing advances in NIPT technologies may lead to more comprehensive solutions in the future. The authors do not advocate for changes in Danish guidelines at this time but remain committed to monitoring technological and clinical developments in prenatal screening. [Extracted from the article]

Objective: To determine whether vaginal progesterone reduces spontaneous preterm birth (sPTB) before 37 weeks in asymptomatic high-risk women with a singleton pregnancy and normal mid-gestation cervical length. Study design: Databases were searched (from inception to December 2020) with the search terms "progesterone" and "premature birth" or "preterm birth". Studies were screened and included if they assessed vaginal progesterone compared to placebo in women with normal cervical length. Data were pooled and synthesized in a meta-analysis using a random effects model. Data sources: MEDLINE and Embase databases. Study synthesis: Following PRISMA screening guidelines, data from 1127 women across three studies were available for synthesis. All studies had low risk of bias and were of high quality. The primary outcome was sPTB <37 weeks, with secondary outcomes of sPTB <34 weeks. Vaginal progesterone did not significantly reduce sPTB before 37 weeks, or before 34 weeks with a relative risk (RR) of 0.76 (95% CI 0.37-1.55, p = .45) and 0.51 (95% CI 0.12-2.13, p = .35), respectively. Conclusions: Vaginal progesterone does not decrease the risk of sPTB in high-risk singleton pregnancies with a normal mid-gestation cervical length. [ABSTRACT FROM AUTHOR]

This article describes the successful implementation of a population-based screening and assessment service for pregnant women in a remote healthcare setting in Australia. The service, called the Initial Maternity Assessment and Planning (IMAP) service, was expanded to include a remote Australian maternity healthcare setting using a co-design approach and implementation science methodology. Since its establishment in 2023, over 200 women have been seen through the service, resulting in an increase in the proportion of local women accessing first trimester ultrasound and a decrease in the number of local women not attending for antenatal care within the first trimester. This study demonstrates the feasibility of scaling up a service to improve equity of care for women in regional and remote areas. [Extracted from the article]

This article describes the establishment of the Initial Maternity Assessment and Planning Service (IMAP) in Australia, which aims to provide comprehensive and early antenatal care for women planning public maternity care. The service includes a comprehensive ultrasound assessment, screening for aneuploidy and pre-eclampsia, and a review of obstetric, medical, and personal history with a dedicated midwife. The information is collated by an obstetrician to provide early pregnancy risk stratification. This study confirms the feasibility of a redesigned approach to first trimester specialist maternity care. [Extracted from the article]

This article discusses the implementation outcomes of the Initial Maternity Assessment and Planning (IMAP) service in Australia. The IMAP service is a first trimester population-based screening and assessment service that aims to improve antenatal care. The study found that a majority of eligible women accessed the service within the recommended gestational window, and a significant proportion were allocated to low-risk community-based models of care. The findings suggest that the IMAP service has successfully improved the provision of early pregnancy care and highlights the potential benefits of a redesigned approach to first trimester specialist maternity care. [Extracted from the article]