Obesity, insulin resistance and fertility: unresolved questions and emerging insights

Purpose of review Obesity significantly impacts fertility in women, contributing to hormonal imbalances, ovulatory dysfunction, and poor reproductive outcomes. This is especially pronounced in polycystic ovary syndrome (PCOS), where obesity and insulin resistance exacerbate fertility challenges. Moreover, obesity is a risk factor for type 2 diabetes (T2D) and gestational diabetes (GDM), further complicating reproductive health. Effective weight loss interventions before conception are essential to improve fertility and reduce the risks of adverse perinatal outcomes, such as GDM, hypertensive disorders, and neonatal complications. Recent findings Lifestyle modifications, including modest calorie restriction and exercise, improve ovulatory function and pregnancy rates but have limited impact on live-birth rates during fertility treatments. Very low-calorie diets (VLCDs) achieve rapid weight loss but raise concerns about maternal nutrition. Pharmacotherapy offers modest benefits for weight loss and fertility, though teratogenic risks persist. Bariatric surgery often results in significant weight loss and enhanced fertility, yet requires careful timing and management of potential nutrient deficiencies. Summary Weight-loss interventions show promise in addressing obesity-related fertility issues, but long-term outcomes and optimal strategies remain unclear. Further research is needed to bridge these gaps and improve reproductive outcomes following weight reduction.