Efficacy of recombinant human follicle stimulating hormone at low doses in inducing spermatogenesis and fertility in hypogonadotropic hypogonadism

Abstract

Recombinant-FSH (rFSH) added to hCG at dose of 450 IU weekly is effective in inducing spermatogenesis in patients with hypogonadotropic hypogonadism (HH), but there are no data on the use of lower doses. This observational retrospective study evaluated whether 150-225 IU of rFSH weekly were able to induce spermatogenesis in HH men who failed to start it with hCG alone. Thirty-four patients with pre-pubertal onset HH (20-44 yr old) without adverse fertility factors were considered for this study. After hCG pre-treatment they received also either rFSH (Group 1) or highly purified urinary FSH (hpFSH) (Group 2) 75 IU sc 2 or 3 times weekly. Semen analysis was performed every 3 months during pre-treatment and the 1st yr of combined therapy. Patients were also invited to refer pregnancies in their partners during the subsequent 12 months. Total sperm count/ejaculate did not show significant difference between 2 groups, while a significantly higher forward motility was observed in Group 1 (p<0.05). The median times to achieve sperm output thresholds (first sperm appearance, sperm concentration >1.5 or >5 mil/ml) were significantly lower in Group 1 (p<0.04, 0.03, and 0.001, respectively). A tendency to a shorter time to pregnancy was shown in partners of Group 1. Our data indicate that lower rFSH week dose than that so far used was able to induce potentially fertilizing sperm output in HH men previously treated with hCG. The rFSH effects are comparable to those of hpFSH but with a trend to a faster outcome achievement.