Objective: To monitor pregnancies in women with pre-existent insulin dependent diabetes for pregnancy loss, congenital malformations, and fetal growth in a geographically defined area of north west England. Design: Population cohort study. Setting: 10 maternity units in Cheshire, Lancashire, and Merseyside which had no regional guidelines for the management of pregnancy in diabetic women. Subjects: 462 pregnancies in 355 women with insulin dependent diabetes from the 10 centres over five years (1990-4 inclusive). Main outcome measures: Numbers and rates of miscarriages, stillbirths, and neonatal and postneonatal deaths; prevalence of congenital malformations; birth weight in relation to gestational age. Results: Among 462 pregnancies, 351 (76%) resulted in a liveborn infant, 78 (17%) aborted spontaneously, nine (2%) resulted in stillbirth, and 24 (5%) were terminated. Of the terminations, nine were for congenital malformation. The stillbirth rate was 25.0/1000 total births (95% confidence interval 8.9 to 41

In an unselected population, the infants of women with pregestational Type 1 diabetes mellitus have 6.4 times the reported risk of a congenital malformation and 5.1 times the reported risk of perinatal mortality than infants in the general population. Further improvements in the management of diabetes and pregnancy in these women are needed if the St Vincent's Declaration target is to be met.

No abstract