From condoms to the pill, the most popular methods of birth control have been around for decades. But according to UCSF population researcher Doctor Joe Spidel, many are still hit and miss, "For example, the pill, about one out of ten women on the pill will get pregnant every year, and that's a lot of failures."
Spidel says implantable ID's have a better record. As do vasectomies for men. But now, one Bay Area woman believes there is even better way -- a kind of injectable sperm stopper that could last indefinitely.
"And it's a polymer gel that's injected into the vas deferens, which is the tube that sperm swims through," birth control advocate Elaine Lissner said.
According to Lissner, the substance was discovered by a scientist in India who was experimenting with water filtration. When injected into a tube, along with an activating agent, the polymer, now known as Vasalgel, solidifies into a sponge-like plug. A demonstration of the procedure shows a liquid containing led powder pass through the microscopic pores in the plug, but the led itself is filtered out. Lissner says the concept is the same in the body.
"It's almost like Swiss cheese or sponge-like in structure," Lissner said. "So fluid can get through and there's no back pressure, which is nice compared to a vasectomy, but sperm are too big to make it through."
She says a doctor makes a small incision in the skin of scrotum, and injects the Vasalgel directly into the vas deferens, where it solidifies and adheres to the surrounding tissue. The procedure which amounts to a no-snip vasectomy, takes less than an hour.
A multiyear study of men in India claimed nearly a 100 percent success rate when the surgery was performed correctly. But in the U.S., trials for Vasalgel are still in animal models, and the system is not yet FDA approved.
Since the polymer can also be dissolved by injecting a second chemical, Lissner's team is hoping to eventually market it as an easier, reversible option for younger men who may want to have children later in life.
"Some men aren't ready to take the final snip," Lissner said. "So this gives men an option, but also for child spacing."
If the animal models are successful, the group hopes to apply for permission to do human testing as early as next year.
As for the question of interest in a new male birth control, Lissner says her group has a database of more than 7,000 people who've requested information in the event human trials are eventually approved.
Written and produced by Tim Didion