Pregnancy Outcomes in Women Without Gestational Diabetes Mellitus Related to the Maternal Glucose Level: Is there a continuum of risk?

OBJECTIVE: To examine selected pregnancy outcomes in women without gestational diabetes mellitus to see whether there was a continuum of risk related to the maternal glucose level. RESEARCH DESIGN AND METHODS: Consecutive women attending two prenatal clinics and three obstetricians in private practice were tested for GDM at the beginning of the third trimester using a 75-g glucose load in the fasting state. The rate of induction, the number of assisted deliveries, the presence of pregnancy-induced hypertension, fetal birth weights, and morbidity were examined with respect to the maternal 2-h glucose level. RESULTS: Data were available for 1,441 women with a 2-h glucose level < 8.0 mmol/l (144 mg/dl). For each 1.0 mmol/l (18 mg/dl) increase in the glucose level, the odds in favor of an assisted delivery increased by 15.2%, and the odds in favor of the baby being admitted to a special care nursery (SCN) increased by 22.6%. There was no significant association between maternal glucose levels and the probability of either pregnancy-induced hypertension or a large-for-gestational-age (LGA) baby after adjustment for other variables. CONCLUSIONS: In normal women there is a continuum of risk related to the maternal glucose level 2 h after a glucose tolerance test for the probability of having an assisted delivery and the likelihood of the baby being admitted to an SCN. The chance of having pregnancy-induced hypertension or a LGA baby also increased as the maternal glucose level increased but could be largely explained by an increasing body mass index.