FSH Treatment for Normogonadotropic Male Infertility: A Synergistic Role for Metformin?

OBJECTIVE: The aim of this paper is to evaluate the effectiveness of follicle-stimulating hormone (FSH) administration in a cohort of insulin resistant (HOMA>2.5) patients with normogonadotropic idiopathic infertility. PATIENTS AND METHODS: We subdivided patients in two clinical groups basing on the adopted therapeutic scheme: group A (n=44) received 150 units of FSH three times a week for three months (group A); group B (n=35) received 150 units of FSH three times a week for three months and 500 mg of slow-release metformin once a day for three months (group B). We evaluated the post-treatment sperm parameters, sperm parameters normalization rate, spontaneous pregnancy rate, and sperm DNA fragmentation normalization rate. RESULTS: 40% of group A patients and 45% of group B patients became normozoospermic after the treatment, while 30% of group A patients and 32% of group B patients achieved a spontaneous pregnancy. B group patients also obtained higher sperm DNA fragmentation normalization rate (45% vs. 33%, p = 0.03). Compared to group A, group B showed a higher sperm concentration, progressive motility and morphology (p < 0.0001). CONCLUSIONS: The results of this study suggest that the addition of the low-dose slow-release metformin in insulin-resistant patients with normogonadotropic infertility improves the efficacy of FSH therapy.