Objective To investigate maternal, perinatal, and neonatal outcomes of pregnancies in women with type 1 diabetes in the Netherlands.
Design Nationwide prospective cohort study.
Setting All 118 hospitals in the Netherlands.
Participants 323 women with type 1 diabetes who became pregnant between 1 April 1999 and 1 April 2000.
Main outcome measures Maternal, perinatal, and neonatal outcomes of pregnancy.
Results 84% (n = 271) of the pregnancies were planned. Glycaemic control early in pregnancy was good in most women (HbA1c 7.0% in 75% (n = 212) of the population), and folic acid supplementation was adequate in 70% (n = 226). 314 pregnancies that went beyond 24 weeks' gestation resulted in 324 infants.