Women taking various forms of hormonal contraceptives can likely combine them safely with antiretrovirals (ARVs), whether as HIV treatment or in the form of Truvada (tenofovir disoproxil fumarate/emtricitabine) as pre-exposure prophylaxis (PrEP) against the virus. The one ARV that may cause problems with such forms of birth control is Sustiva (efavirenz), which is included in Atripla (efavirenz/tenofovir disoproxil fumarate/emtricitabine).

Researchers conducted a systematic review of scientific studies published through September 2015, ultimately reviewing 50 reports from 46 studies of women using hormonal contraceptives and ARVs at the same time, whether for treatment or as PrEP. Investigators looked for changes in effectiveness and toxicity of both types of drugs, as well as how the drugs are metabolized, including changes in drug levels in the body.

The study authors found that whether used as treatment or prevention, most ARVs have limited interactions with hormonal contraceptives. The standout was Sustiva. The limited data available suggest that this ARV, and by extension Atripla, may compromise the effectiveness of hormonal birth control, with the exception of Depo-Provera (depot medroxyprogesterone acetate). Despite any interactions with Sustiva, birth control implants in particular remain very effective when paired with the drug.

Hormonal contraceptives do not apparently affect levels of ARVs in the blood or their effectiveness.

According to the available data, taking PrEP does not reduce the effectiveness of hormonal contraceptives or vice versa.

Kavita Nanda, MD, MHS, director of medical research at FHI 360 in Durham, North Carolina, and the study’s lead author, says most ARVs, whether taken for HIV treatment or as PrEP, “can be used concurrently with hormonal contraceptives without risk of drug interactions. HIV-positive women should continue to be offered contraceptive options that best meet their needs.”