Abstract
INTRODUCTION: Polycystic ovary syndrome (PCOS) is a common endocrine disorder that affects fertility and metabolism. Obesity, present in a significant proportion of PCOS patients, exacerbates insulin resistance (IR) and worsens reproductive outcomes. This study explores the effects of a 12-week 5:2 intermittent fasting diet with meal replacement (MR) on body weight, metabolic, and endocrine markers in obese women with PCOS. METHODS: A non-randomized, single-arm interventional study was conducted with 90 obese women diagnosed with PCOS. Participants were assigned to three groups: 5:2 intermittent fasting with MR, non-meal replacement intermittent fasting, and no intervention. To reduce potential confounding, the study utilized Propensity Score Matching (PSM) to match baseline characteristics such as age, body mass index (BMI), and metabolic markers. Primary outcomes included changes in body weight, BMI, waist circumference, fasting insulin, glucose levels, and reproductive hormone markers. Menstrual regularity and ovulation frequency were also assessed. RESULTS: The intervention group (5:2 intermittent fasting with MR) showed significant reductions in body weight (from 77.15 kg to 69.1 kg, P < 0.001), waist circumference, and BMI. Insulin resistance (HOMA-IR) decreased significantly (P = 0.008), and a reduction in 2-hour glucose levels (P = 0.025) was observed. Although metabolic markers improved, reproductive hormones (follicle-stimulating hormone [FSH], luteinizing hormone [LH], estradiol, progesterone) did not show significant changes. However, menstrual regularity improved in 80% of participants, and 50% showed improved ovulation frequency. The non-meal replacement intermittent fasting group also showed improvements, but to a lesser extent. CONCLUSIONS: The 5:2 intermittent fasting diet with MR significantly reduces body weight, improves insulin sensitivity, and enhances metabolic markers in obese women with PCOS. Although reproductive hormone levels did not significantly change, menstrual and ovulatory function improved. Future studies with larger sample sizes and longer follow-up are needed to explore the long-term effects of intermittent fasting on reproductive health in PCOS patients.