Effect of maternal obesity on neonatal death in sub-Saharan Africa: multivariable analysis of 27 national datasets.

Background: Rates of obesity are increasing worldwide, including in sub-Saharan Africa. Neonates born to obese mothers in low-income settings are at increased risk of complications including admission to neonatal intensive care, macrosomia, low Apgar scores, and perinatal death. We investigated whether maternal obesity is a risk factor for neonatal death in sub-Saharan Africa and the effect on the detailed timing of death within the neonatal period.

Methods: Cross-sectional Demographic and Health Surveys from 27 sub-Saharan countries (2003-09) were pooled. We used multivariable logistic regression to assess the risk of neonatal death (in women's most recent singleton livebirth in the 5 years preceding the survey) by maternal body-mass index (BMI) category (measured during the survey). Timing of death was investigated with a discrete-time survival model.

Findings: 15,518 of 81,126 eligible women were overweight (4266 were obese), 52,006 had an optimum BMI, and 13,602 were underweight. Maternal obesity was associated with an increased odds of neonatal death after adjustment for confounding factors (adjusted odds ratio 1·46, 95% CI 1·11-1·91). Maternal obesity was a significant risk factor for neonatal deaths occurring during the first 2 days of life (1·62, 1·11-2·37). We noted no statistically significant relation later in the neonatal period (days 2-6 1·36, 0·84-2·21; days 7-27 1·19, 0·65-2·18), possibly because of low statistical power.

Interpretation: Maternal obesity in sub-Saharan Africa is associated with increased risk of early neonatal death. Potential mechanisms include prematurity, intrapartum events, or infections. Strategies to prevent and reduce obesity need to be considered; obese women should be advised to deliver in a health-care facility that can provide emergency obstetric and neonatal care.

Funding: Economic and Social Research Council.