Scientists at Cornell University may be closing in on the long-sought “holy grail” of male contraception: a safe, reversible, nonhormonal method that completely halts sperm production. In a breakthrough mouse study, researchers used a compound called JQ1 to temporarily shut down meiosis—the critical process that produces sperm—without causing lasting harm. After treatment stopped, sperm production bounced back, fertility returned, and the animals produced healthy offspring.
I was a donor to that project, and right now I think there are still concerns about the long-term reversibility. The project isn’t dead but I doubt we will see it as a readily available option for the public within the next decade, if ever.