Maternal weight, pregnancy weight gain, and the risk of antepartum stillbirth

OBJECTIVE: This study investigated whether the risk of antepartum stillbirth increases with body mass index during early pregnancy and also investigated the association between weight gain during pregnancy and the risk of antepartum stillbirth.Study Design: This population-based case-control study included 649 women with antepartum stillbirths and 690 control subjects among Swedish nulliparous women. RESULTS: Compared with lean mothers (body mass index < or = 19.9 kg/m2), the odds ratios for risk of antepartum deaths were as follows: normal weight (body mass index, 20.0-24.9 kg/m2) odds ratio, 1.2 (95% confidence interval, 0.8-1.7); overweight (body mass index 25.0-29.9 kg/m2), odds ratio, 1.9 (95% confidence interval, 1.2-2.9); and obese (body mass index > or = 30.0 kg/m2) odds ratio, 2.1 (95% confidence interval, 1.2-3.6). For term antepartum death corresponding risks were even higher, with odds ratios of 1.6 (95% confidence interval, 0.9-2.6) for normal weight, 2.7 (95% confidence interval, 1.5-5.0) for overweight, and 2.8 (95% confidence interval, 1.3-6.0) for obese women, respectively. Maternal weight gain during pregnancy was not associated with risk of antepartum stillbirth. CONCLUSION: Maternal overweight condition increased the risk of antepartum stillbirth, especially term antepartum stillbirth, whereas weight gain during pregnancy was not associated with risk.