Obesity is known to contribute to anovulation, menstrual irregularities and sub-fertility. Furthermore, obese women who do become pregnant are at increased risk of miscarriage and obstetric complications including pregnancy-induced hypertension, preeclampsia, gestational diabetes, fetal macrosomia, and neonatal and maternal mortality. Outcomes for those undergoing IVF treatment are consistently poorer for obese individuals, and the offspring of obese women are at higher risk of becoming obese themselves and of developing heart disease, diabetes and other metabolic conditions later in life. The complex deregulatory effects of excess weight upon hormone production are thought to play a part in many of these issues.

There are various recommendations regarding the timing of planned pregnancy after weight loss surgery which are based on a theoretical understanding of what occurs after the operation. A truly controlled scientific study evaluating the risk and benefit of pregnancy after surgical weight loss is difficult to design. We employ a common sense approach based on surgical literature as well as an understanding of the changes that occur after surgical operations for weight loss.