Hormonal contraception and HIV acquisition: reanalysis using marginal structural modeling

Hormonal contraceptives are used widely worldwide; their effect on HIV acquisition remains unresolved. We reanalyzed data from the Hormonal Contraception and HIV Study using marginal structural modeling to reduce selection bias due to time-dependent confounding. Replicating our original analysis closely, we found that depomedroxyprogesterone acetate (DMPA) but not combined oral contraceptive (COC) was associated with increased HIV acquisition. Also, young (1824 years) but not older women who used DMPA and COCs were at increased HIV risk.