This contraceptive intended for safe sex actually puts users at risk of AIDS. Find out how safe you are after the jump.
Emma RABID

The most popular contraceptive for women in eastern and southern Africa, a hormone shot given every three months, appears to double the risk the women will become infected with H.I.V., according to a large study published Monday. And when it is used by H.I.V.-positive women, their male partners are twice as likely to become infected than if the women had used no contraception.
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.

Injectable hormones are very popular. About 12 million women between the ages of 15 and 49 in sub-Saharan Africa, roughly 6 percent of all women in that age group, use them. In the United States, it is 1.2 million, or 3 percent of women using contraception. While the study involved only African women, scientists said biological effects would probably be the same for all women. But they emphasized that concern was greatest in Africa because the risk of H.I.V. transmission from heterosexual sex was so much higher there than elsewhere.

“The best contraception today is injectable hormonal contraception because you don’t need a doctor, it’s long-lasting, it enables women to control timing and spacing of birth without a lot of fuss and travel,” said Isobel Coleman, director of the women and foreign policy program at the Council on Foreign Relations. “If it is now proven that these contraceptions are helping spread the AIDS epidemic, we have a major health crisis on our hands.”

The study, which several experts said added significant heft to previous research while still having some limitations, has prompted the World Health Organization to convene a meeting in January to consider if evidence is now strong enough to advise women that the method may increase their risk of getting or transmitting H.I.V.

“We are going to be re-evaluating W.H.O.’s clinical recommendations on contraceptive use,” said Mary Lyn Gaffield, an epidemiologist in the World Health Organization’s department of reproductive health and research. Before the meeting, scientists will review research concerning hormonal contraceptives and women’s risk of acquiring H.I.V., transmitting it to men, and the possibility (not examined in the new study) that hormonal contraceptives accelerate H.I.V.’s severity in infected women.

“We want to make sure that we warn when there is a real need to warn, but at the same time we don’t want to come up with a hasty judgment that would have far-reaching severe consequences for the sexual and reproductive health of women,” she said. “This is a very difficult dilemma.”

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