How effective are lifestyle interventions for overweight women trying to conceive?

To summarize and critically review the current knowledge on the effectiveness of lifestyle modifications for overweight women trying to conceive.

Overweight is associated with a wide spectrum of disorders, which may directly or indirectly affect fertility [from menstrual cycle irregularities to a lower chance of live birth after assisted reproductive technology (ART) treatment]. Weight loss through nonpharmaceutical lifestyle interventions is achievable. Weight loss can normalize menstrual cycle irregularities and can increase fecundability. Pregnancy-associated risks, such as gestational diabetes can be decreased by preconception weight reduction.

Weight loss through lifestyle changes (i.e., lower caloric intake and increased physical activity), may increase fecundability and may have a positive impact on the course of pregnancy, delivery, and neonatal outcomes. Accordingly, women should be motivated to reduce their weight before conception. However, the effectiveness of life-style intervention programs for women actively seeking medical support in achieving pregnancy has not convincingly been demonstrated. In the few randomized controlled trials (RCTs), selection bias for trial participation by patient motivation may have been present, yet participant attrition was still high and mean effects were small, casting doubts on the utility of such programs in routine care. Pharmacological and surgical intervention may be more effective or necessary complements to lifestyle intervention programs.