How birth control makes you susceptible to HIV
Many women who use hormonal birth control have probably heard reports that it may leave them susceptible to HIV. A new study explains why and sheds light on which birth control methods may be better for some women as opposed to others.
First, the science
A study in mBio, a journal of the American Society for Microbiology, explained why injectable contraceptive depot medroxyprogesterone acetate (Depo-Provera injection) is associated with an increased risk of HIV infection.
"Before this study, there were all these controversial reports, some showing that DMPA increases the risk of HIV infection and others showing it doesn't, and there was no biologic explanation for the differences between studies," said Dr. Raina Fichorova, lead author and director of the genital tract biology division at Brigham and Women's Hospital. "This new study offers an explanation for the inconsistent studies, and it lies in the microbial communities of the reproductive tract."
Fichorova’s team examined cervical swabs from 823 women between 18 and 35 years old. All of the women tested negative for HIV.
The women were split into three groups: those who used DMPA, those who used estrogen-progesterone oral contraceptives and those who used no hormonal contraceptives. Researchers looked at results in all of the groups to see which women had a healthy vaginal environment and which had a disturbed vaginal environment.
The team wanted to know if women taking oral contraceptives or DMPA were at a higher risk for immunological changes, which can increase their vulnerability to HIV infection, than women not on a hormonal contraceptive. They found that DMPA use was associated with an increase in these immunological changes and that the presence of certain vaginal infections further increased this risk. Women with disturbed vaginal settings — including vaginal infections — were at an increased risk for HIV vulnerability.
The researchers concluded that concurrent infections or disturbed vaginal microbiota may worsen the suppression of the immune system by DMPA, thus adding to a woman's vulnerability to HIV.
"Women deserve to know more, so that they can make informed choices about birth control,” Fichorova said.
So, which birth controls may make you vulnerable?
The birth control types mentioned in this study include:
- DMPA — that’s the Depo-Provera injection
- Estrogen-progestin oral contraceptives
According to Drugs.com, these include the following: Alesse, Apri, Aviane, Beyaz (combination), Brevicon, Cryselle, Cyclessa, Demulen, Desogen, Enpresse, Estrostep, Femcon, Kariva, Lessina, Levlen, Levlite, Levora, Lo Ovral, Loestrin, LoSeasonique, Low-Ogestrel, Lybrel, Microgestin, Mircette, Modicon, Mononessa, Necon, Nelova, Nordette, Norinyl, Nortrel, NuvaRing, Ogestrel, Ortho Evra, Ortho Tri-Cyclen, Ortho-Cept, Ortho-Cyclen, Ortho-Novum, Ovcon, Ovral, Portia, Safyral (combination) , Seasonale, Seasonique, Sprintec, Tri-Levlen, Tri-Norinyl, Triphasil, Tri-Sprintec, Trivora, Yasmin, Yaz and Zovia.
Are you at increased risk?
- Healthy vag and no contraceptives: According to the study, if you have a healthy vagina without infections and are not taking a hormonal contraceptive, you are not at an increased risk.
- Healthy vag and taking contraceptives: Women taking birth control — whether it’s the shot or other estrogen-progesterone contraceptives — should bring these concerns to their doctors, as they could be more at risk. Of course, if you’re not engaging in behavior that puts you at risk for HIV in general, this may not be a concern.
- Unhealthy vag (recent infections, poor microbiota) and taking contraceptives: According to the study, this group is at an increased risk for HIV. That said, if women in this group are not engaged in behavior that could cause HIV, it may not be a concern for them.
“Hormonal contraception can increase the risk for having an asymptomatic abnormal vaginal environment, which can in turn alter vaginal immunity and theoretically increase the risk for HIV infection,” Dr. Serena Chen — director of the division of reproductive endocrinology in the department of obstetrics and gynecology at Saint Barnabas Medical Center in New Jersey — told SheKnows.
Chen said the research gives a plausible explanation to the link between hormonal contraception and HIV susceptibility… something that otherwise had yet to be explained.