The findings potentially present an alarming quandary for women in Africa. Hundreds of thousands of them suffer injuries, bleeding, infections and even death in childbirth from unintended pregnancies. Finding affordable and convenient contraceptives is a pressing goal for international health authorities.
But many countries where pregnancy rates are highest are also ravaged by H.I.V., the virus that causes AIDS. So the evidence suggesting that the injectable contraceptive has biological properties that may make women and men more vulnerable to H.I.V. infection is particularly troubling.