Converting Men From Clomiphene Citrate to Natesto for Hypogonadism Improves Libido, Maintains Semen Parameters, and Reduces Estradiol.

Objective: To evaluate outcomes including libido, semen parameters, testosterone, estradiol (E2), follicle stimulating hormone (FSH), and luteinizing hormone when converting men with low libido on Clomiphene Citrate (CC) to Natesto.

Methods: A retrospective chart review was performed. Baseline hormones prior to treatment, and again on CC and Natesto, as well as semen parameters on CC and on Natesto were assessed.

Results: In 41 men, there was no difference in serum testosterone levels on CC vs Natesto, however; there was a significantly higher E2 on CC than on Natesto. Although FSH levels were significantly lower on Natesto than at baseline, the mean FSH level on Natesto remained in the normal reference range. There was no difference in luteinizing hormone levels at baseline vs on Natesto. There was not a significant difference in semen parameter values when men were on CC vs when they were on Natesto for 3 months. At 3 months after changing to Natesto, 38 of 41 (92.7%) men reported significantly improved libido on Natesto when compared to CC.

Conclusion: Men on CC and Natesto reach eugonadal testosterone levels, however; on CC the E2 level nearly doubled from baseline, and converting men from CC to Natesto returned E2 to nearly baseline levels. There was not a detrimental effect on semen parameters, and there was subjective reporting of improved libido after converting from CC to Natesto in this cohort, but further long-term studies are needed prior to Natesto being established as a definitive treatment for hypogonadism for men desiring to maintain fertility.