Use of hormonal contraceptives and HIV acquisition in women: a systematic review of the epidemiological evidence.

Whether or not the use of hormonal contraception affects risk of HIV acquisition is an important question for public health. We did a systematic review, searching PubMed and Embase, aiming to explore the possibility of an association between various forms of hormonal contraception and risk of HIV acquisition. We identified 20 relevant prospective studies, eight of which met our minimum quality criteria. Of these eight, all reported findings for progestin-only injectables, and seven also reported findings for oral contraceptive pills. Most of the studies that assessed the use of oral contraceptive pills showed no significant association with HIV acquisition. None of the three studies that assessed the use of injectable norethisterone enanthate showed a significant association with HIV acquisition. Studies that assessed the use of depot-medroxyprogesterone acetate (DMPA) or non-specified injectable contraceptives had heterogeneous methods and mixed results, with some investigators noting a 1·5-2·2 times increased risk of HIV acquisition, and others reporting no association. Thus, some, but not all, observational data raise concern about a potential association between use of DMPA and risk of HIV acquisition. More definitive evidence for the existence and size of any potential effect could inform appropriate counselling and policy responses in countries with varied profiles of HIV risk, maternal mortality, and access to contraceptive services.