Effects of metformin on clinical and biochemical parameters in polycystic ovary syndrome.J Reprod Med. 2004 May; 49(5):361-7.JR
To assess the effects of 6 months of metformin therapy on clinical and biochemical parameters in polycystic ovary syndrome (PCOS) and to evaluate those parameters in responders and nonresponders to identify the subjects who respond to an insulin sensitizer in PCOS.
Sixty-six diagnosed PCOS patients were recruited. Baseline characteristics (menstrual history, hirsutism scoring, acne grading, body mass index [BMI], serum luteinizing hormone and follicule-stimulating hormone [LH/FSH] ratio, testosterone,fasting insulin and glucose/insulin index) were assessed initially and 6 months after metformin therapy. Three groups were constructed on the basis of menstrual symptoms: oligomenorrhea (group I), amenorrhea (group II) and hypomenorrhea (group III). Responders were those who had improvements in menstrual pattern or conceived. Response was compared in 3 groups, and biochemical parameters were compared in responders and nonresponders.
There were 44 (66.6%) oligomenorrheic, 17 (25.7%) amenorrheic and 5 (7.5%) hypomenorrheic cases and 31 (46.5%) infertile women. In total, 85.7% responded to treatment; the rest (14.3%) were nonresponders. Among responders, 62.29% achieved regular periods, 22.95% experienced improvements in their menstrual abnormalities, and 13% conceived. Overall, a significant reduction occurred in BMI (P =.04), mean testosterone (P = .03) and mean fasting insulin levels (P = .01), but no significant improvement was observed in hirsutism, acne, LH/FSH ratio or glucose/insulin index. A total of 9.75%, 18.75% and 30% did not respond in the oligomenorrheic, amenorrheic and hypomenorrheic groups, respectively (P = .04). Testosterone and insulin were reduced significantly in responders (P = .05 and .01, respectively) but not in nonresponders (P = .26 and .73). An initial high LH/FSH ratio and lower testosterone levels were associated with a better response.
Six months of metformin therapy improved menstrual cyclicity and fertility in women with PCOS. It resulted in a decline in testosterone and insulin levels. Oligomenorrheic patients with an increased LH/FSH ratio and lower testosterone levels responded better.