Gestational diabetes versus obesity as risk factors for pregnancy‐induced hypertensive disorders and fetal macrosomia

Objective To assess whether obesity and/or gestational diabetes mellitus (GDM) are independent risk factors for fetal macrosomia and/or pregnancy‐induced hypertensive disorders. Design Retrospective computerised database review. Setting Lyell McEwin Health Service, South Australia. Sample All nulliparous women delivering singleton babies in the years 1999 and 2000 Main outcome measures Birth weights, the occurrence of fetal macrosomia, gestational hypertension and preeclampsia were compared between 258 normoglycaemic women (control group), 76 women with only an abnormal glucose challenge test, and 51 women with GDM. Results Only GDM with fasting hyperglycaemia is a risk factor for macrosomia (risk ratio: 3.3 95% confidence limits 1.229–8.736). Smoking is associated with a decrease in the incidence of pregnancy‐induced hypertensive disorders. Conclusions Our data strongly suggest that GDM and obesity are not independent risk factors for pregnancy‐induced hypertensive disorders.