The influence of the introduction of a national prenatal screening program on late termination of pregnancy, a retrospective cohort study.

OBJECTIVE: To assess the influence of a national prenatal screening program on category 1 (lethal anomalies) late terminations of pregnancy (LTOP). METHODS: In this population-based retrospective cohort study, we included all category 1 LTOPs from 2004 to 2015 in the Netherlands. The number of LTOPs before and after the introduction of the program was compared as well as the diagnostic process and factors contributing to LTOP. RESULTS: In total, 97 LTOPs were reported. After the introduction of the program, the number of LTOPs decreased from 17 per year to 5 per year on average. The number of cases in which the diagnostic process started with obstetric indications decreased from 55% to 17% (p < 0.01) and the number of cases detected by routine screening increased from 11% to 52% (p < 0.01). Four factors still contributed to LTOP after the introduction of the screening program: diagnostic or parental delay (40%), absence of screening (24%), false negative results of prior screening (14%) and late onset of disease (12%). CONCLUSION: The number of LTOPs decreased after the introduction of the screening program. At present, the diagnostic process is mostly screening driven. Parental- and diagnostic delay is still an important factor that contributes to LTOP.

Prenatal sonographic features can accurately determine parental origin in triploid pregnancies.

OBJECTIVE: To describe the prenatal sonographic features and maternal biochemical markers in triploid pregnancies and to assess whether prenatal phenotype can determine genetic origin. METHODS: We performed a retrospective multicenter cohort study that included all triploid pregnancies diagnosed between 2000 and 2018 in two Fetal Medicine Units in Amsterdam. Fetal growth, presence of structural anomalies, extra-fetal anomalies, and maternal biochemical markers were retrieved. Asymmetrical intrauterine growth restriction was diagnosed when the head-to-abdominal circumference (HC/AC) ratio was >95th centile. Parental origin was analyzed via molecular genotyping in 46 cases (38.3%). RESULTS: One hundred and twenty triploid pregnancies were identified, of which 86 cases (71.6%) were detected before 18 weeks of gestation. Triploidy of maternal origin was found in 32 cases (69.6%) and was associated with asymmetrical growth restriction, a thin placenta, and low pregnancy-associated plasma protein A and free beta-human chorionic gonadotrophin (ß-hCG) levels. Triploidy of paternal origin was found in 14 cases (30.4%) and was associated with an increased nuchal translucency, placental molar changes, and a high free ß-hCG. Prospective prediction of the parental origin of the triploidy was made in 30 of the 46 cases based on phenotypical ultrasound presentation, and it was correct in all cases. CONCLUSION: Asymmetrical growth restriction with severe HC/AC discrepancy is pathognomonic of maternal triploidy. Placental molar changes indicate a paternal triploidy. Moreover, triploidy can present with an abnormal first trimester combined test, with serum levels on the extreme end. When available results of maternal serum markers can support the diagnosis of parental origin of the triploidy, an accurate assessment of the parental origin based on prenatal sonographic features is possible, making DNA analysis redundant.