It’s coming: a male contraceptive that isn’t sold in rest-room vending machines. No fewer than three male birth control methods are presently being tested. In a nine-country study published last April, weekly injections of testosterone prevented conception in 98.6 percent of 399 couples. An outside source of testosterone fools the pituitary into thinking the testes are making too much of the hormone. In response, the pituitary stops releasing two other hormones that stimulate sperm and testosterone production, and the sperm count drops to nil.
Physical side effects are thus far minimal: mild acne and a few pounds of weight gain. But do the injections turn men into macho jerks? Everybody’s partner thinks they’re jerks once in a while, so it’s a little hard to sort that out, says study coauthor William Bremner of the Veterans Affairs Medical Center in Seattle. If you take a bunch of normal men and their ...
