Motivation towards first trimester screening for preeclampsia among pregnant women in Denmark: A cross-sectional questionnaire study.

INTRODUCTION: The aim of this cross-sectional questionnaire study was to investigate motivation to participate in a possible new screening for preeclampsia in the first trimester of pregnancy among Danish pregnant women through a questionnaire based on Theory of Planned Behavior developed for this specific purpose. The new screening combines maternal characteristics with mean arterial pressure, uterine artery pulsatility index and biochemical markers to predict the risk of preeclampsia, whereas the current Danish screening uses maternal characteristics alone. MATERIAL AND METHODS: Participation was offered to a proportion of women attending a first or a second trimester screening scan at two University Hospitals in Copenhagen. The questionnaire was set up in REDCap® and answers were entered directly into the database, which was accessed via a QR-code. RESULTS: We invited 772 pregnant women to participate in the questionnaire survey between November 2021 and April 2022 at Copenhagen University Hospital Rigshospitalet (study site one) (n = 238) and Copenhagen University Hospital Hvidovre (study site two) (n = 534). The response rate was 71.8% (171/238) at study site one and 33.9% (181/534) at study site two. A total of 352 women were included in the study (total participation rate 45.6%). Most women had a positive attitude towards preeclampsia screening in pregnancy, and 99.4% said they would participate in a risk assessment for preeclampsia if given the opportunity. A total of 97.4% answered "yes" to whether a first trimester preeclampsia screening should be offered to all pregnant women in Denmark. Positive motivation to participate in preeclampsia screening was correlated with having a network with a positive attitude towards preeclampsia screening. CONCLUSIONS: The results of this study indicate that Danish pregnant women have a positive attitude towards participation in a first trimester screening for preeclampsia. This observation might be useful in relation to possible future implementation in Denmark.

Cell-Free Fetal DNA in the Early and Late First Trimester.

OBJECTIVE: The aim of this work was to investigate the association between maternal and fetal characteristics and the fetal fraction at 8-14 weeks' gestation, with emphasis on the change in the fetal fraction upon repeat sampling. METHOD: One sample for cell-free DNA (cfDNA) testing was collected at the same time as the biochemical markers for combined first trimester screening (visit 1) and another at the nuchal translucency scan (visit 2). Chromosome-selective cfDNA analysis was performed on frozen plasma. RESULTS: Overall, 321 women were included at visit 1, and 307 had a repeat blood sampling. A fetal fraction was obtained in 532 samples (238 samples with repeat fetal fraction). The fetal fraction decreased with maternal BMI (p < 0.001), was lower in Asian women (p = 0.03), and increased with ß-hCG levels (p < 0.001) and gestational age (p = 0.04). Before 10 weeks' gestation, the fetal fraction was lower (p = 0.02), as was the probability of a sufficient fetal fraction (p = 0.03) after adjustment for maternal BMI. Asian women had a higher increase in fetal fraction upon repeat sampling (p < 0.001). CONCLUSION: Before 10 weeks' gestation, the fetal fraction is significantly lower but seems to increase more rapidly compared to later gestations. Presently, combined first trimester screening with cfDNA testing should not include samples before 10 weeks' gestation.

Parental Decisions about Prenatal Screening and Diagnosis among Infants with Trisomy 21 in a National Cohort with High Uptake of Combined First-Trimester Screening.

INTRODUCTION: The aim was to investigate the parental decisions about prenatal screening and diagnosis among infants with trisomy 21 (T21) in a national cohort with high uptake of combined first-trimester screening (cFTS). MATERIAL AND METHODS: This was a nationwide population-based study including infants born in 2009-2012. Information from the cFTS, fetal karyotype results and pregnancy outcome was obtained from the Danish Fetal Medicine Database on all women with a cFTS risk assessment. Cut-off for referral for invasive testing was ≥1:300. Karyotype results from pregnancies with no cFTS were obtained from the Danish Cytogenetic Central Registry. RESULTS: The uptake rate of cFTS was 91.6%, and 82.8% (8,032/9,704) of the screen-positive women opted for invasive testing. Overall, 82.2% (454/552) chose to terminate an affected pregnancy. In the 4-year period, 102 of 232,962 singletons were born alive with T21. The cFTS risk was true-positive, false-negative or not obtained in 21.6, 48.0 and 30.4%, respectively, of these pregnancies. DISCUSSION: In this large national cohort, 4.4 per 10,000 live-born infants had T21. Of 102 infants with T21 from 2009 to 2012, 52.0% were born after the women had not opted for cFTS or were true-positive but declined invasive testing or termination, and 48.0% were born after a false-negative risk assessment.

Women with chromosomally normal male fetuses are at increased risk of being referred for invasive testing following first-trimester risk assessment.

OBJECTIVE: This study investigated the gender distribution in karyotype results from chorionic villus samples and amniocenteses performed due to an increased risk for Down syndrome based on first-trimester combined risk assessment. METHODS: All prenatal karyotypes performed from 2006-2008 due to a risk assessment above 1:300 were retrieved from the Danish Central Cytogenetic Register. The distribution of gender for all newborns was obtained from Statistics Denmark. The χ(2) test and odds ratios were used for intergroup comparison. RESULTS: We retrieved 5 157 karyotype results (54.9% male and 45.1% female karyotypes), of which 4 662 were normal. During the same period, 100 112 boys and 94 732 girls were born. Women carrying male fetuses were significantly more often referred for invasive testing than women carrying female fetuses (2.8 vs. 2.5%, p < 0.0001). However, the proportion of chromosomally normal male fetuses was significantly greater than that for female fetuses (92.0 vs. 88.4%, p < 0.0001). CONCLUSION: A significantly higher proportion of women pregnant with male fetuses compared with female fetuses had an invasive diagnostic test performed prenatally following a risk assessment for Down syndrome.