A prospective double-blind, randomized, placebo-controlled study to evaluate the efficacy of silodosin 8mg as an on-demand, reversible, nonhormonal oral contraceptive for males: a pilot study.

Abstract

As silodosin 8mg, used for treating BPH, is known to cause absence of sperms in the ejaculate, its potential as an on-demand, reversible, nonhormonal oral contraceptive for males was assessed in this pilot study. In this randomized, double-blind, placebo-controlled pilot study, healthy, sexually active adult male volunteers in a stable sexual relationship with a female partner with proven fertility were recruited. Those using other contraceptive methods were excluded. During the first part of the study, silodosin 8mg and placebo were crossed over among the randomly assigned two groups of participants and their post-masturbation semen and post-ejaculation urine were analyzed for spermatozoa. During the second part, both groups received silodosin 8mg 3h prior to heterosexual vaginal intercourse for 1year. The primary outcome measure was the number of unintended pregnancies in their female partners. The secondary outcome measure was dropout rate due to adverse events. The clinical trial registry number was CTRI/2017/09/009872. The study period was January 2017 to December 2017 with sample size 63. Reversible azoospermia was noted following silodosin intake during the first part of the study. During the second part, no untended pregnancy was reported. None of the participants dropped out due to adverse events. Four patients were lost to follow-up. Silodosin 8mg achieved total reversible azoospermia, hence prevented unintended pregnancies in the female partners of the males who used the drug as an on-demand oral contraceptive.