Performance of first trimester screening for Trisomy 21 in twin pregnancies.

OBJECTIVES: To assess the performance of the Danish first trimester screening program in twin pregnancies. METHOD: Retrospective, nation-wide, cohort study with data collected from the Danish Fetal Medicine Database (DFMD) and The Danish Central Cytogenetic Registry (DCCR). The cohort included all women with twin pregnancies participating in the national first trimester screening program for Trisomy 21. Risk assessment was based on maternal age, nuchal translucency (NT) thickness and, if available, biochemical markers (ß-hCG and PAPP-A). RESULTS: 8812 twin pregnancies including 42 pregnancies with Trisomy 21 had a risk assessment between 2009 and 2017. The detection rate (DR) for pregnancies with a risk assessment based on maternal age and NT only (missing data on biochemical markers, n = 4693) was 69.6% (95% CI: 50.8%-88.4%) for a 6.3% false positive rate (FPR) (95% CI: 5.6%-7.0%), whereas for pregnancies with a risk assessment based on all three parameters (n = 4119) the DR was 89.5% (95% CI: 76.7%-100.0%) for a 7.2% FPR (95% CI: 6.4%-8.0%). CONCLUSION: The DR of Trisomy 21 in twin pregnancies, seems as high as for singleton pregnancies, when using optimal screening techniques, but the FPR is nearly twice as high.

High risk-What's next? A survey study on decisional conflict, regret, and satisfaction among high-risk pregnant women making choices about further prenatal testing for fetal aneuploidy.

OBJECTIVES: To investigate decision making among pregnant women when choosing between noninvasive prenatal testing, invasive testing, or no further testing. METHODS: Women with a high-risk result from the first trimester screening were invited to fill in two online questionnaires at gestational age 12 to 14 (Q1) and 24 weeks (Q2). The scales used were Decisional Conflict and Regret Scales, Satisfaction with genetic Counselling Scale, and Health-Relevant Personality Inventory. RESULTS: Three hundred thirty-nine women agreed to participate, and the response rates were 76% on Q1 and 88% on Q2. A percentage of 75.4% chose an invasive test, 23.8% chose noninvasive prenatal testing (NIPT), 0.4% chose no further testing, and 0.4% had both NIPT and invasive testing. Among all participants, 13.3% had a high level of decisional conflict. We found that choosing NIPT was associated with a high decisional conflict (p = 0.013), receiving genetic counselling the same day was associated with a high decisional conflict (p = 0.039), and a high satisfaction with the genetic counselling was associated with low decisional conflict (p < 0.001). Furthermore, the personality subtrait "alexithymia" was associated with low decisional conflict (p = 0.043). There was a significant association between high decisional conflict and later decisional regret (p = 0.008). CONCLUSION: We present evidence that satisfaction with and timing of counselling are important factors to limit decisional conflict. Interestingly, women choosing NIPT had more decisional conflict than women choosing invasive testing.