Vasalgel injections prevent pregnancies in monkeys. But will the method work in humans—and would you be willing to try it?
It’s 2017, and your options for male contraception are essentially limited to condoms (which aren’t always foolproof) and a vasectomy (which is, y’know, pretty extreme). But right now, scientists are hurtling full speed toward a viable, long-term birth control option for men, according to new research published in Basic and Clinical Andrology.
Sounds good, right? Now for the part that’ll have you cradling your, um, man bits: It works by injecting gel right into the testicles.
Here’s how the injection, called Vasalgel, works: Instead of snipping, sealing, or clamping the tubes from each testicle (called vas deferens), you’d get an injection (under anesthesia) of the sticky gel, which barricades your swimmers from escaping. The plugged-up sperm then gets reabsorbed in your body.
For the record, this concept isn’t exactly new. A similar injectible hydrogel, RISUG—short for Reversible Inhibition of Sperm Under Guidance—was tested in men back in 2003. While occasional sperm made their way through, no pregnancies were reported from the 25 subjects. RISUG works by permeating sperms’ membranes and disintegrating them; to reverse the effects, a doctor injects a different polymer that flushes the gel out. RISUG has made it to later stages of trials and testing.
But here’s the other question: Would you be willing to try Vasalgel?
So far, the only test subjects have been monkeys. In the study, researchers injected 16 adult rhesus monkeys with Vasalgel. After recuperating for one week, the monkeys were released to outdoor group housing where they were left to shack up with female monkeys for a breeding season.
There were few complications—namely the improper placement of the injection in one monkey, the formation of a sperm granuloma (a lump of sperm that leaks or gets forced out of the blocked tube, which is common among men who get vasectomies), and the unrelated castration of another monkey who lost in a biting fight to another. (We seriously doubt and hope you’d ever encounter this, but hey: science).
Overall, the Vasalgel was entirely effective in preventing the monkeys from conceiving. Next steps will include making sure scientists can reverse the effects of Vasalgel, so the monkeys—and, the theory goes, willing humans—can regain their fertility.