Pregnancy outcomes in mothers with pregestational diabetes: A population-based study in North Rhine (Germany) from 1988 to 1993

The purpose of this study was to estimate the proportion of pregnancies with pregestational diabetes in Germany, to compare the outcome of these pregnancies to pregnancies in nondiabetic mothers and to identify risk factors for poor pregnancy outcomes in mothers with pregestational diabetes. Data of the ''Perinatalerhebung Nordrhine'' from 1988-1993 were analysed. The Perinatalerhebung is an ongoing quality assurance programme of prenatal and perinatal care in the region of North Rhine (South Western part of North Rhine-Westphalia). During the observation period a proportion of 93%-100% of the annual births in the region (n = similar to 100000) were included in the study. Their data had been documented by the obstetricians in a standard multiple choice questionnaire. The outcome parameters perinatal mortality, macrosomia, prematurity, and malformations were analysed in relation to several defined explanatory variables. There were 2,402 births in mothers with pregestational diabetes (0.4% of all births). The proportions of poor pregnancy outcomes in women with pregestational diabetes were 2.8% for perinatal mortality, 27.6% for macrosomia, 21.1% for prematurity and 2.1% for malformations. The respective relative risks compared to the non diabetic mothers were 4.3 (95% CI 3.4-5.5) for perinatal mortality, 3.1 (95% CI 2.9-3.3) for macrosomia, 2.7 (95% CI 2.5-2.9) for prematurity and 1.7 (95% CI 1.3-2.3) for malformations. The main risk factor for perinatal mortality in children of diabetic mothers after adjustment for maternal smoking, ethnicity, parents' professional achievement, type of obstetric hospital, and maternal age was substandard use of prenatal care. Conclusions The prevalence of births from mothers with pregestational diabetes and their pregnancy outcomes were similar to those in other Western countries. The standard for non-diabetic mothers has not been reached yet. Further improvements may be achieved if all diabetic women are convinced to use the standard prenatal care facilities throughout pregnancy.