In this episode, host Rachel Feltman speaks with freelance science journalist Hannah Seo about a promising new development in male contraception: a hormone-free birth control pill that reversibly stops sperm production has just passed its first human safety trial. Seo explains how the drug works, what makes it different from hormone-based methods and where it stands in clinical development.

Recommended reading:

First Hormone-Free Male Birth Control Pill Shown Safe in Early Human Trial

Male Birth Control Is in Development, but Barriers Still Stand in the Way

“Safety and Pharmacokinetics of the Non-Hormonal Male Contraceptive YCT-529,” by Nadja Mannowetz et al., in Communications Medicine, Vol. 5, Article No. 279. Published online July 22, 2025

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Science Quickly is produced by Rachel Feltman, Fonda Mwangi, Kelso Harper and Jeff DelViscio. This episode was edited by Alex Sugiura. Shayna Posses and Aaron Shattuck fact-check the show. The theme music was composed by Dominic Smith.

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