Male Contraceptive Pill Found 99% Effective In Mice

A team of scientists said Wednesday they had developed a male oral contraceptive that was 99 percent effective in mice and didn't cause observable side effects, with the drug expected to enter human trials by the end of this year.
The findings will be presented at the American Chemical Society's spring meeting, and mark a key step towards expanding birth control options -- as well as responsibilities -- for men.

Ever since the female birth control pill was first approved in the 1960s, researchers have been interested in a male equivalent, Md Abdullah Al Noman, a graduate student at the University of Minnesota who will present the work, told AFP.

"Multiple studies showed that men are interested in sharing the responsibility of birth control with their partners," he said -- but until now, there have been only two effective options available: condoms or vasectomies.

Vasectomy reversal surgery is expensive and not always successful.

The female pill uses hormones to disrupt the menstrual cycle, and historic efforts to develop a male equivalent targeted the male sex hormone testosterone.

The problem with this approach, however, was that it caused side effects such as weight gain, depression and increased levels of cholesterol known as low-density lipoprotein, which increases heart disease risks.

The female pill also carries side effects, including blood-clotting risks -- but since women face becoming pregnant in the absence of contraception, the risk calculation differs.