Obesity and stillbirth

• The risk of stillbirth increases with body mass index (BMI), especially at or after term gestation.
• The mechanism of the association between stillbirth and obesity remains unclear.
• Obesity is associated with other risk factors for stillbirth such as diabetes.
• Weight reduction should be considered before and between pregnancies.
• The safety of weight loss interventions during pregnancy is unclear.

Recent years have witnessed a rise in maternal obesity, which is independently associated with an increased risk of stillbirth. The pathophysiology is unclear, but it is likely related to abnormal placental function, and inflammatory, metabolic and hormonal imbalances in the mother. Obesity is associated with conditions such as diabetes, which can also cause stillbirth. In order to reduce the risk of obesity-associated stillbirth, women of reproductive age should be actively encouraged to optimise their pre-pregnancy weight as the safety of weight loss interventions during pregnancy is unproven. Obese and extremely obese women should be treated as high-risk obstetric patients, with increased antenatal surveillance and specialist input. The postnatal period may be a useful time to provide weight management advice to women to prevent interpregnancy weight gain and reduce the risk of stillbirth in subsequent pregnancies.