USE OF METFORMIN IN NON-DIABETIC PATIENTS WITH POLYCYSTIC OVARY SYNDROME: HORMONAL EFFECTS

Abstract

This prospective, single‐arm study investigated the endocrine effects of metformin in 50 non‐diabetic women with polycystic ovary syndrome (PCOS) over 12 weeks. Participants (age 18–35 years; BMI 18.5–29.9 kg/m²) meeting Rotterdam criteria and exhibiting normal glucose tolerance received metformin 500 mg three times daily, with adherence assessed by pill counts. Fasting blood samples collected at baseline and study end quantified total testosterone, free androgen index (FAI), sex hormone–binding globulin (SHBG), luteinizing hormone (LH), follicle‐stimulating hormone (FSH), insulin, and glucose; insulin resistance was estimated via HOMA‐IR. Metformin treatment yielded a 30.2% reduction in total testosterone (61.2 ± 9.8 to 42.7 ± 7.1 ng/dL; p < 0.001) and a 43.1% decrease in FAI (5.1 ± 1.0 to 2.9 ± 0.7; p < 0.001), accompanied by a 38.3% rise in SHBG (40.7 ± 4.9 to 56.3 ± 6.2 nmol/L; p < 0.001). LH declined by 14.8% (8.1 ± 1.4 to 6.9 ± 1.1 IU/L; p < 0.001) while FSH increased by 10.2% (4.9 ± 0.9 to 5.4 ± 0.8 IU/L; p = 0.005). HOMA‐IR improved by 22.2% (2.7 ± 0.6 to 2.1 ± 0.5; p < 0.001), and reductions in HOMA‐IR correlated strongly with decreases in FAI (r = 0.72) and total testosterone (r = 0.68; both p < 0.001). Full adherence was achieved by 80% of participants, and adverse events were mild. These findings demonstrate that metformin safely and effectively ameliorates hyperandrogenism and insulin resistance in non‐diabetic PCOS patients, supporting its role as a primary endocrine modulator across diverse PCOS phenotypes.