Metformin to restore normal menses in oligo-amenorrheic teenage girls with polycystic ovary syndrome (PCOS)

Purpose; To describe our clinical experience in using Metformin combined with a high protein-low carbohydrate diet to restore normal menstrual cycles in teenaged females with polycystic ovary syndrome (PCOS). Methods: To enter the study, patients had to have well-documented PCOS, be oligo- (six cycles or less in the preceding year) or amenorrheic (absence of menstrual cycles for 1 year), and not have exclusionary diseases or drugs. Accompanying a high protein-low carbohydrate diet, Metformin (1.5-2.55 g/day) was given for 10.5 +/- 6.4 months (range, 4.5-26.5 months). Follow-up every 8-10 weeks for greater than or equal to 6 months was scheduled with interval history, review of menstrual status, assessment of any Metformin-related side effects, brief physical examination, and determination of weight and blood pressure. Results: All 11 girls had normal fasting blood glucose and glycohemoglobin. Pre-Metformin, five girls were amenorrheic, three had only one menstrual cycle in the previous year, and three had greater than or equal to 6 cycles/year. With Metformin, 10 of 11 girls (91%) resumed regular normal menses; 39% of 38 follow-up visits with regular normal menstrual cycles were ovulatory with normal luteal-phase serum progesterone (greater than or equal to 2.3 ng/mL). Of the 11 girls, nine (82%) lost weight; five girls lost greater than or equal to 11 lb and seven lost greater than or equal to 5 lb. After adjusting for weight reduction, with Metformin, estradiol and progesterone rose (p = .0014,.027, respectively) (changes consistent with resumption of regular normal menses), total plasma cholesterol fell (p = .026), and there was a downward trend in testosterone (p = .068). Conclusion: Metformin safely ameliorates the endocrinopathy of PCOS in previously oligo-amenorrheic teenage females with PCOS, facilitating resumption of normal menses in most girls. (C) Society for Adolescent Medicine, 2001.