Changes in Menstrual Regularity and Associated Factors in Women With Obesity Without PCOS Following Bariatric Surgery

This study aimed to analyze the independent risk factors for irregular menstrual cycles in women with obesity without polycystic ovary syndrome (PCOS), describe the changes in menstrual cycle regularity after bariatric surgery, and explore the influencing factors of these changes. A retrospective analysis was conducted on 430 women with obesity patients without PCOS who underwent either laparoscopic sleeve gastrectomy (LSG) or laparoscopic Roux-en-Y gastric bypass (LRYGB) at the First Affiliated Hospital of Jinan University between January 2019 and January 2022. Patients were categorized into a regular group (n = 200) and an irregular group (n = 230) based on the regularity of their preoperative menstrual cycles. Demographic data, anthropometric indicators, and laboratory parameters were collected preoperatively and at 1, 3, 6, and 12 months postoperatively. Propensity score matching (1:1) and unconditional logistic regression analysis were employed to identify risk factors. After propensity score matching, elevated C-peptide (OR = 1.487, 95% CI: 1.187 - 1.863, p = 0.001) and serum ferritin (SF) (OR = 1.006, 95% CI: 1.000 - 1.013, p = 0.041) were identified as independent risk factors for preoperative irregular menstrual cycles. In contrast, elevated progesterone (OR = 0.895, 95% CI: 0.830 - 0.965, p = 0.004) was a protective factor. The incidence of irregular menstrual cycles decreased from 53.5% preoperatively to 22.6% at 12 months postoperatively. In the irregular group, higher C-peptide levels at 1 month, larger hip circumference at 3 months, and higher aspartate aminotransferase (AST) levels at 12 months were associated with persistent irregularity. Laparoscopic sleeve gastrectomy (LSG) demonstrated a more significant improvement in menstrual regularity than LRYGB within 1 year (p < 0.05). The study concluded that bariatric surgery effectively improves menstrual cycle regularity in women with obesity without PCOS. C-peptide, SF, and progesterone are key factors affecting preoperative menstrual regularity, while dynamic changes influence postoperative recovery in metabolic and anthropometric indicators.