The Effect of Bariatric Surgery on Female Reproductive Function

Field: Medicine (Health Sciences)

Overweight, obesity, and central adiposity are wellrecognized as contributors to female infertility, traditionally attributed to menstrual disturbances, aggravation of ovulatory disorders such as polycystic ovary syndrome (PCOS), alteredoocyteandembryoquality, and abnormal endometrial physiology (1). They are also associated with worsened obstetric outcomes including miscarriage, congenital abnormalities, preeclampsia, and gestational diabetes. The first line of therapy for overweight and obesity is through weight management, which is known to improve a range of surrogate and clinical markers of fertility and outcomes of pregnancy (2). In keeping with this, international guidelines recommend that obese women achieve a healthy weight and that obese women lose a modest amount of weight before pregnancy. However, long-term maintenance of a reduced weight is extremely difficult, with studies reporting that approximately only 15% of subjects undergoing weight loss interventions maintain either their reduced weight or an overall reduction of 9–11 kg at a follow-up time of up to 14 yr (3). Pharmacological and surgical treatments are thus increasingly assessed as additional strategies for prepregnancy weight management, particularly in combination with lifestyle (diet, exercise, and behavioral) strategies or after lifestyle strategies have proved unsuccessful. In this issue of the JCEM, Legro et al. (4) report on hormonal and body composition before and after substantial weight loss after gastric bypass surgery and question the traditional explanations for infertility in obese women. Bariatric surgery includes a variety of gastrointestinal surgical procedures such as gastric banding, gastric bypass including Roux-en-Y, biliopancreatic diversion, and sleeve gastrectomy with varying mechanisms of effect (restriction vs. malabsorptive), effectiveness, and complications. It results in greater weight loss than conventional nonsurgical management in obesity and improvements in outcomes or resolution of clinical conditions such as PCOS, type 2 diabetes mellitus, cardiovascular disease, and risk factors including the metabolic syndrome, glycemic control, hypertension, and dyslipidemia, sleep apnea, mortality, quality of life, and fertility (5–9). This indicates the potential for both acute improvements in fertility and long-term maintenance of obesity-associated morbidities. A number of guidelines for bariatric surgery recommend eligibility with a body mass index (BMI) of at least 40 kg/m, or at least 35 kg/m if present with other comorbid conditions in conjunction with prior weight management programs (10). With respect to fertility, the 2009 American Congress of Obstetrician and Gynecologists clinical practice guidelines do not specifically recommend bariatric surgery (11). Recent Australian evidence-based guidelines for the management of PCOS, as the largest contributor to anovulatory infertility, recommend that PCOS be considered an additional obesity-related morbidity that improves significantly with weight reduction, and that a lower BMI range for initiation of bariatric surgery (BMI 35 kg/m) could be considered (12). Importantly, this guideline highlights the importance of considering this approach as second-line therapy for improvement of fertility outcomes in women with PCOS who are anovulatory and who remain infertile after intensive multidisciplinary lifestyle management for a minimum of 6 months. Obesity is usually proposed to be associated with infertility because of hormonal aberrations resulting in men-