Impact of Laparoscopic Sleeve Gastrectomy on Menstrual Regularity and Spontaneous Pregnancy in Morbidly Obese Women: A Retrospective Cohort Study

<i>Background and Objectives</i>: Obesity is a major contributor to female reproductive dysfunction, frequently resulting in menstrual irregularity, anovulation, and subfertility. Bariatric surgery improves metabolic health; however, its effect on reproductive outcomes-particularly the shift from assisted to spontaneous conception-remains incompletely defined. This study aimed to evaluate the impact of laparoscopic sleeve gastrectomy (LSG) on menstrual cycle regularity and spontaneous pregnancy rates in women of reproductive age. <i>Materials and Methods</i>: This retrospective observational study included 52 women aged 18-40 years who underwent LSG between January 2013 and October 2017. Self-reported menstrual history, as documented during routine preoperative assessment in the electronic medical records, and reproductive outcomes (including spontaneous and assisted conception) were compared between the preoperative and postoperative periods. The median follow-up duration was 38 months. <i>Results</i>: A significant improvement in menstrual regularity was observed (46.2% to 94.2%, <i>p</i> < 0.001). Among women attempting conception, 10/15 (66.7%) achieved spontaneous pregnancy; one conceived via ART. Notably, 57.1% of all pregnancies occurred within the first 12 months post-surgery, including three unintended conceptions. Additionally, among women who conceived spontaneously, four had a history of requiring assisted reproductive technologies (ART), including two who had previously failed to conceive despite ART treatment. <i>Conclusions</i>: LSG is associated with significant normalization of menstrual cycles and a qualitative shift toward spontaneous conception in morbidly obese women. The rapid return of fertility, which may exceed patient awareness, underscores the importance of comprehensive perioperative counseling regarding effective contraception to prevent unintended pregnancies during the active weight-loss phase.