A new review of research suggests that women using the injectable contraceptive depot-medroxyprogesterone acetate or DMPA might be at higher risk of HIV infection by as much at 40%.
Medical researchers at the University of Alabama at Birmingham in the United States, the University of Cape Town in South Africa and McMaster University in Canada examined the underlying biological mechanisms that could contribute to greater risk of HIV infection for certain hormonal contraceptives. They also examined animal, cell and biochemical research on medroxyprogesterone acetate, which is the main component of DMPA, to find that it acts differently from other forms of progestin used in contraceptives. In the cells of the genital tract that can come in contact with HIV, medroxyprogesterone acetate behaves like the stress hormone cortisol, which is an immunosuppressant, possibly causing decreases in immune function and interfering with the protective barrier function of the female genital tract.
The researchers say that the findings offer an explanation as to why there has been an increased rate of HIV infection. New formulations that administer 31% less hormone to offset the immunosuppressive effect of DMPA have been tested but it has been found the authors of the review conclude that even though it is likely to result in a partial reduction of concentration of the hormone shortly after delivery, it is not likely to ameliorate the overall negative impact of medroxyprogesterone on biological responses.
The authors suggest that other forms of birth control should rapidly replace DMPA shots. They also emphasise that DMPA should be replaced and not just removed from shelves so that women in sub-Saharan Africa and other high risk regions where DMPA is used are not left without contraceptive options. DMPA is used by an estimated 50 million women worldwide. India introduced DMPA into its family planning programme in July 2017, despite the objection of health activists who pointed to possible side effects and the manner in which full information will be given and informed consent received from large numbers of poorly educated women that the programme targets.
The study was published in the journal Endocrine Reviews.