Objective: To estimate whether the incidences of adverse fetal and neonatal outcomes in infants of mothers with preexisting types 1 and 2 diabetes 1) differ from infants of nondiabetic mothers in Nova Scotia (NS); and 2) have changed between 1988 and 2002.
Methods: Population-based cohort study using the NS Atlee Perinatal Database, a well-validated source of standardized clinical information.
Results: A total of 516 infants of diabetic mothers and 150,589 infants of nondiabetic mothers from singleton pregnancies were studied. Infants of diabetic mothers had significantly higher rates of perinatal mortality (17.4/1,000 compared with 5.9/1,000, relative risk [RR] 3.01, 95% confidence interval [CI] 1.55-5.84), major congenital anomaly (9.1% compared with 3.1%, RR 2.97, 95% CI 2.25-3.90), and large for gestational age birth (LGA, more than 90th percentile weight for gestational age) (45.2% compared with 12.6%, RR 3.59, 95% CI 3.26-3.95) than infants of nondiabetic mothers. In infants of diabetic mothers, there was no improvement in perinatal mortality (23.4/1,000 in 1988-1995 compared with 11.5/1000 in 1996-2002, P = .340), incidence of LGA (48.0% in 1988-1995 compared with 42.3% in 1996-2002, P = .237), or rate of major congenital anomaly (8.2% in 1988-1995 compared with 10.0% in 1996-2002, P = .560). Diabetes remained an independent risk factor for LGA infants and major congenital anomaly after adjusting for possible confounders.
Conclusion: Rates of adverse neonatal outcomes are 3-9 times greater in infants of diabetic mothers compared with those of nondiabetic mothers. There were no significant improvements in rates of perinatal mortality, congenital anomaly, or LGA birth in infants of diabetic mothers in 1996-2002 compared with 1988-95.