A new study in The Lancet Infectious Diseases reports that the use of hormonal contraception may double the risk of HIV transmission. But, at best, what this study shows is that transmission of HIV through conventional heterosexual contact occurs rarely, if ever.
The study… involved 3,800 couples in Botswana, Kenya, Rwanda, South Africa, Tanzania, Uganda and Zambia. In each couple, either the man or the woman was already infected with H.I.V. Researchers followed most couples for two years, had them report their contraception methods, and tracked whether the uninfected partner contracted H.I.V. from the infected partner… The study found that women using hormonal contraception became infected at a rate of 6.61 per 100 person-years, compared with 3.78 for those not using that method. Transmission of H.I.V. to men occurred at a rate of 2.61 per 100 person-years for women using hormonal contraception compared with 1.51 for those who did not.
The Times further reports that,
The researchers recorded condom use, essentially excluding the possibility that increased infection occurred because couples using contraceptives were less likely to use condoms.
Regardless, condom use was self-reported, and so ever-dubious. It’s quite possible/likely that couples using hormonal contraception were less likely to adhere to the condom regimen. Additionally, the results were not adjusted for type of sexual activity.
As there were only 73 women who seroconverted (out of 1,314) and only 13 women who seroconverted in the hormonal contraception using group, there is certainly enough uncertainty in self-reported condom use and type of sexual activity to question the claim that hormonal contraception plays any physiological role in risk of HIV infection.