Effect of Metformin in adolescents with polycystic ovary syndrome

Background: Polycystic ovary syndrome (PCOS) is a frequent endocrine disorder affecting females in reproductive age and adolescent girls, frequently presenting with hyperandrogenism, menstrual irregularities, and metabolic dysfunction. Aim: To evaluate the effect of metformin on ovulatory function, hormonal profiles, and hyperandrogenic features in adolescent girls with PCOS. Patients and Methods: A prospective randomized controlled study was performed on 120 adolescent girls aged 15–18 years with PCOS attending Mansoura University Hospital. Participants have been randomly assigned to receive either 850 milligrams metformin tow times per day (Group A) or placebo (Group B) for 6 months. Clinical assessments included menstrual pattern, hirsutism (via Ferriman–Gallwey score), and acne. Hormonal and metabolic evaluations included LH, FSH, TSH, prolactin, testosterone, fasting insulin, glucose, HOMA-IR, and serum progesterone on cycle days 21. Results: Metformin significantly reduced LH (47%) and testosterone (22.1%) levels compared to placebo (p<0.001, p=0.003). Fasting insulin and HOMA-IR also diminished significantly in the metformin group (p<0.001). Serum progesterone levels and menstrual regularity improved, with oligomenorrhea declining from 52% to 18% (p=0.015). However, changes in FSH, TSH, prolactin, and hirsutism scores were not statistically significant. Conclusion: Metformin therapy significantly improves ovulatory and metabolic variables in adolescents with PCOS but has limited effects on hirsutism and other hormonal markers, suggesting the need for individualized treatment strategies and longer follow-up.