Gonadotropin Therapy Once a Week for Spermatogenesis in Hypogonadotropic Hypogonadism.

Objective: Hypogonadotropic hypogonadism (HH) can be caused by congenital HH (CHH), pituitary stalk interruption syndrome (PSIS), and pituitary injury (acquired HH). Gonadotropin therapy, typically administered every other day or twice a week, is commonly used to promote spermatogenesis. The aim of this retrospective study was to evaluate the efficacy of weekly gonadotropin therapy on spermatogenesis in patients with HH (n = 160).

Methods: The patients' diagnoses include Kallmann syndrome (KS) (n = 61), normosmic CHH (nCHH) (n = 34), PSIS (n = 48), and acquired HH (n = 17). The rate of successful spermatogenesis and median time to achieve spermatogenesis among these 4 subgroups were compared as well as between a weekly group (n = 95) and a twice-a-week group (n = 223) of CHH patients.

Results: Once-a-week gonadotropin therapy resulted in 74% (119/160) of HH patients achieving spermatogenesis with significantly increased testicular volume and total testosterone levels (P < .001). The median period of spermatogenesis was 13 (interquartile range[IQR] 11.4-14.6) months. Larger basal testicular volume (P = .0142) was an independent predictor for earlier sperm appearance. Six spontaneous pregnancies occurred. Compared with the twice-a-week regimen for spermatogenesis, the weekly injection group had a similar median time of sperm appearance (14 [IQR, 11.6-16.4] vs 15 [IQR, 13.5-16.5] months), success rate (78% [74/95] vs 64% [143/223]), sperm concentration (20.9 [IQR, 5.0-46.3] vs 11.7 [IQR, 2.1-24.4] million/mL), and progressive sperm motility (40.8 ± 27.3% vs 36.9% ± 20.2%).

Conclusion: Weekly gonadotropin therapy is effective in inducing spermatogenesis, similar to that of twice-a-week therapy. A larger basal testicular size was a favorable indicator for earlier spermatogenesis.