The Danish Fetal Medicine Database: establishment, organization and quality assessment of the first trimester screening program for trisomy 21 in Denmark 2008-2012.

OBJECTIVE: To describe the establishment and organization of the Danish Fetal Medicine Database and to report national results of first-trimester combined screening for trisomy 21 in the 5-year period 2008-2012. DESIGN: National register study using prospectively collected first-trimester screening data from the Danish Fetal Medicine Database. POPULATION: Pregnant women in Denmark undergoing first-trimester screening for trisomy 21. METHODS: Data on maternal characteristics, biochemical and ultrasonic markers are continuously sent electronically from local fetal medicine databases (Astraia Gmbh software) to a central national database. Data are linked to outcome data from the National Birth Register, the National Patient Register and the National Cytogenetic Register via the mother's unique personal registration number. First-trimester screening data from 2008 to 2012 were retrieved. MAIN OUTCOME MEASURES: Screening performance was assessed for the years 2008-2012 by calculating detection rates and screen-positive rates. RESULTS: A total of 268 342 first-trimester risk assessments for trisomy 21 were performed in singleton pregnancies. Participation rate in first-trimester screening was >90%. The national screen-positive rate increased from 3.6% in 2008 to 4.7% in 2012. The national detection rate of trisomy 21 was reported to be between 82 and 90% in the 5-year period. CONCLUSION: A national fetal medicine database has been successfully established in Denmark. Results from the database have shown that at a national level first-trimester screening performance for trisomy 21 is high with a low screen-positive rate and a high detection rate.

Risk for developmental coordination disorder correlates with gestational age at birth.

BACKGROUND: Studies suggest that children born very preterm have a high risk of developmental coordination disorder (DCD). We examined the relation between the larger spectrum of gestational age at birth and the risk of DCD. METHODS: We used the 7-year follow-up data from 22898 singletons in the Danish National Birth Cohort. We calculated a total score from the Developmental Coordination Disorder Questionnaire (DCDQ), incorporated in the 7-year follow-up, and defined children with a score of 46 or below as having probable DCD. Information on gestational age was obtained from the Medical Birth Register. RESULTS: Gestational age at birth was inversely associated with the risk of DCD; a decline in gestational age by a week was associated with a 19% [95% confidence interval 14%, 25%] increased risk of DCD screening positive among children delivered before 40 weeks. No significant increased risk of DCD was seen for children born post-term. CONCLUSION: Our data indicate that short gestational age at birth in a range up to gestational week 37 is related to an increased risk of DCD.

Prenatal risk indicators of a prolonged pregnancy. The Danish Birth Cohort 1998-2001.

BACKGROUND: Few prenatal risk factors of prolonged pregnancy, a pregnancy of 42 weeks or more, are known. The objective was to examine whether sociodemographic, reproductive, toxicologic, or medical health conditions were associated with the risk of prolonged pregnancy. METHODS: Data from the Danish Birth Cohort in Denmark were used. Interview data from 53,392 participants with live-born singleton deliveries in the period 1998-2001 were available at the time of this study. The participants were interviewed by telephone at 12 and 30 weeks' gestation, and 6 and 18 months after delivery. Statistical analyses were done using logistic regression. RESULTS: Women with a pre-pregnancy body mass index of 25 kg/m2 or more had a high risk of prolonged pregnancy. If the pre-pregnancy body mass index was 35 kg/m2 or more the odds ratio was 1.52 (95% CI 1.28-1.82). Nulliparity also increased the risk of prolonged pregnancy (OR (95% CI) = 1.35 (1.27-1.44)). CONCLUSIONS: The risk of post-term delivery was high in women with a pre-pregnancy body mass index of 25 kg/m2 or more, and in nulliparous women.

Genetic influence on prolonged gestation: a population-based Danish twin study.

OBJECTIVE: The purpose of this study was to test a possible genetic component to prolonged gestation. STUDY DESIGN: The gestational duration of single, first pregnancies by both female and male twins was obtained by linking the Danish Twin Registry, The Danish Civil Registration System, and the Danish Medical Birth Register. A total of 2588 same-sex twin pairs of whom both cotwins became parents during 1978 to 1996 were identified. RESULTS: The concordance rate for female twin pairs for a gestation of > or =41 weeks and > or =42 weeks was higher for monozygotic twin pairs than for dizygotic twin pairs, which indicates genetic effects. Biometric modeling suggested that genetic factors account for 23% to 30% of the liability to prolonged gestation. The difference in concordance rate between monozygotic and dizygotic male twin pairs was small, and the best fitting model indicated no genetic factors. CONCLUSION: Maternal genes influence prolonged gestation. However, a substantial paternal genetic influence through the fetus was not found.

Perinatal and maternal complications related to postterm delivery: a national register-based study, 1978-1993.

OBJECTIVE: This study was undertaken to estimate the risk of fetal and maternal complications associated with postterm delivery in Denmark. STUDY DESIGN: A cross-sectional study that used records from the Danish Medical Birth Registry from 1978 to 1993 was performed. All women with registered prolonged pregnancy (n = 78022) and a 5% random sample of all women who gave birth (n = 47021) were linked to the Danish National Discharge Register. We established a postterm group of 77956 singleton deliveries and a term group of 34140 singleton spontaneous deliveries. Logistic regression models were used to analyze data. RESULTS: The risk of perinatal and obstetric complications was high in postterm delivery compared with term delivery (adjusted odds ratios between 1.2 and 3.1). The risk of perinatal death was 1.33 (1.05-1.68). CONCLUSION: Postterm delivery was associated with significantly increased risks of perinatal and maternal complications in Denmark in the period from 1978 to 1993.