Excitement and Questions About Vasalgel

Last week, news spread that a long-sought version of reversible birth control for men had reached a new milestone. Known as Vasalgel, the polymer that is injected into the vas deferens to prevent sperm from passing through, is proving effective in baboons and will soon be tested on humans, according to its developer the Parsemus Foundation.

There were a lot of triumphant headlines - and a few questioning whether the average man will be willing to undergo the procedure - but the fact that the only information I could find about Vasalgel on the internet was sourced from its developer raised my eyebrows a bit. Not that this organization, which focuses its efforts on "neglected research," and its work aren't legitimate, but it seems like a good idea to be skeptical when one press release from a company working on a drug or procedure sets off a cascade of laudatory articles.

There were some interesting pieces that took the skeptic's view, and it seems that an important conversation has been started about the cultural impact a male birth control could have, but what seemed to be missing from a lot of the articles covering this development was a detailed explanation of just how it works.

So I did a little bit of research, and found that the researchers don't seem to be exactly sure themselves. (This is where curiosity overtakes skepticism, for the record. I am not a doctor or a scientist and my skepticism lies solely with the way so many news organizations seem to lap up press releases without digging much deeper. I'm not out to prove anyone wrong or question their methods or motives, only to learn as much as possible about something that intrigues me).

Vasalgel was inspired by RISUG, or Reversible Inhibition of Sperm Under Guidance, a procedure developed by Indian biomedical engineer Sujoy Guha. According to the website for RISUG, within minutes of the polymer being injected into the vas deferens as part of a minimally invasive procedure, it solidifes, clings to the "microscopic folds" of the walls of the vas deferens and essentially kills the sperm by causing a combination of positive and negative charges that make the sperm membranes burst. Probably.

That's the hypothesis confirmed in at least one study Guha conducted with colleagues in 2004, but they aren't 100 percent sure that's what's happening. Of course, one could argue that science is never 100 percent sure about anything, but I just found it interesting that even on the RISUG site, the language says that this is "reportedly" what happens to the sperm.

How exactly the sperm are stopped from leaving the vas deferens and fertilizing an egg may not be important in the scheme of things; if the point is to create a male version of birth control, that it works is what matters. And so far, it seems to, at least with baboons. I'll be excited to watch as more research is done on this; Parsemus just received a new grant from the Packard Foundation, so maybe they will be able to answer some of the questions that others have not yet been able to tackle.