Study finds common contraceptive shot may increase HIV risk

Jan 9 2018

A recent study conducted by researchers at the University of Cape Town, South Africa, found an association between HIV risk and the use of common birth control medications, such as DMPA, among women from sub-Saharan Africa and other high-risk regions.

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The study, which was supported by the National Institutes of Health and the Canadian Institutes of Health Research, was published in the journal Endocrine Reviews.

According to UNAIDS—the Joint United Nations Program on HIV/AIDS, there were 36.7 million people living with HIV around the world in 2016, and more than 50% of them live in eastern or southern Africa.

Dr. Zdenek Hel, a co-author and professor at the University of Alabama at Birmingham Department of Pathology, UAB School of Medicine, explained that the use of depot-medroxyprogesterone acetate (DMPA)—a predominant contraceptive in sub-Saharan Africa  may elevate the risks of HIV infection in exposed women by about 40%.

The increased rate of HIV infection among women using DMPA contraceptive shots is likely due to multiple reasons, including decreases in immune function and the protective barrier function of the female genital tract. Studying the biology of MPA helps us understand what may be driving the increased rate of HIV infection seen in human research. These findings suggest other forms of birth control should rapidly replace DMPA shots.

Dr. Hapgood

However, other forms of contraceptive methods do not show similar adverse impacts on the immune function in cell culture, small animals, or human studies.

DMPA is estimated to be used by more than 50 million women around the world.  It is particularly popular in Alabama and other Southern states in the United States.

In the current study, researchers examined the fundamental biological mechanisms that contribute to increased HIV risk for certain hormonal contraceptives.

According to Dr. Janet P. Hapgood, the lead study author of the study, ensuring women in areas with high rates of HIV infection with the access to affordable contraceptive options is important to protect individual and public health. The risk of HIV transmission can be reduced by increasing the availability of contraceptives that use a different form of female hormone progestin other than the one found in DMPA.

Researchers also examined animal, cell, and biochemical research on the form of progestin used in DMPA—medroxyprogesterone acetate, or MPA. The results showed variations in the functions of MPA from other forms of progestin used in contraceptives, i.e., MPA acts like the stress hormone cortisol in the cells of the genital tract that can come in contact with HIV.

Dr. Hel commented that the access to safe, effective, and affordable birth control medications for women's health worldwide is critical;

Up to 50 percent of unintended pregnancies in Africa end in abortion, often performed in an unsafe manner. We have to do everything in our power to rapidly replace DMPA with a safer alternative. The word 'replace' is critical; DMPA cannot just be taken off the shelves as many women would be left with no available option. Ideally, women should have access to a full range of contraceptive choices and should be informed regarding the benefits and potential dangers associated with each option.

In order to offset the immunosuppressive effect of DMPA, a new formulation called Sayana Press was developed, which administers 31% less hormone through a subcutaneous administration.

The scientists concluded that, even though a lower dose is likely to result in a partial reduction of the systemic concentration of the hormone shortly after delivery, it does not ameliorate the overall negative effects of MPA on biological responses.