FLICKR, JINTERWASThe search for a male contraceptive has led to competitions for better birth control and multimillion dollar investments from Silicon Valley. Now a February 7 study in Basic and Clinical Andrology has shown that Vasalgel, a hydrogel that can be injected into the vas deferens to block sperm, appears to have prevented pregnancy in rhesus monkeys with fewer side effects than a vasectomy.
“Vasectomies are a routine procedure for nonhuman primate veterinarians, so to have similar or even slightly better outcomes trying a brand-new procedure is very encouraging,” coauthor Angela Colagross-Schouten, a veterinarian at the University of California, Davis’s California National Primate Research Center, said in a statement. “Hopefully, Vasalgel placement can be an option for other captive colonies, including zoos, that want to manage reproductive rates while allowing for social housing.”
Vasalgel is a polymer that can be injected into the vas deferens to form a spongy, high molecular–weight hydrogel that allows important bodily fluids, including semen—but not sperm cells—to pass through. In a forthcoming study involving rabbits, Colagross-Schouten said she and her colleagues have demonstrated that the process can be reversed by flushing the hydrogel out ...