Hormonal birth-control injections may double a woman's risk of contracting HIV and passing it on to her partner, according to a new study. The research comes at a time when many governments are looking to scale up their family-planning programmes in a bid to reduce maternal mortality.
Published in the 4 October 2011 online edition of The Lancet's Infectious Diseases journal, the study followed about 3,800 heterosexual couples in seven African countries over about two years. Researchers found that women who relied on hormonal shots to prevent pregnancy doubled their HIV risk. In women who were HIV-positive, using "the shot" doubled the chances that they transmitted HIV to their partners.
Researchers also evaluated the HIV risk associated with birth-control pills. While findings suggest a similar relationship between the pill and HIV risk, study author Jared Baeten of the US University of Washington cautioned that too few women reported using the pill to draw a definite conclusion.
Although participants were not asked to identify which injectable birth control they were receiving, it is likely many were on depot medroxprogeterone acetate (DMPA), according to Baeten. More commonly known by its brand name, Depo-Provera, this drug features in most family-planning programmes in Africa.
Research from South Africa, with an HIV prevalence rate of about 18 percent, has indicated it may also be the most prevalent birth control method aside from condoms.
“Active promotion of DMPA in areas with high HIV incidence could be contributing to the HIV epidemic in sub-Saharan Africa, which would be tragic," said Charles Morrison, senior director for clinical sciences at Family Health International, in a related commentary published in The Lancet.
"Conversely, limiting one of the most highly used effective methods of contraception in sub-Saharan Africa would probably contribute to increased maternal mortality and morbidity and more low birth-weight babies and orphans - an equally tragic result."
The research could mean changes for high prevalence countries like South Africa that are hoping to lower maternal mortality by preventing unplanned pregnancies.
|The study should not stop women from using contraception... it should promote a conversation about how we keep women safe while reducing unplanned pregnancy....|
The study is the first to show a relationship between birth control injections and increased HIV risk, Baeten noted. While it did not investigate how, biologically, hormonal contraception increased HIV risk, participants' cervical swabs showed that HIV-positive women on hormonal contraception had increased HIV levels in their genital tracts, which may explain why their male partners were more likely to contract the virus.
"Truthfully, we don't know perfectly how HIV establishes itself... what happens between exposure and infection," Baeten told IRIN/PlusNews.
"Previous studies have suggested that perhaps contraception can lead to microscopic thinning of the vaginal mucous membrane [and] changes to genital tract... that makes it easier for HIV to establish itself."
Mucous membranes line body parts like the nose, mouth, vagina and anus. HIV can pass through this type of tissue and into the bloodstream, leading to infection. Damage to this membrane is thought to increase this risk.
Morrison urged donors to support a randomized trial to investigate the link between hormonal contraception and HIV.
"The time to provide a more definitive answer to this critical public health question is now; the donor community should support a randomized trial of hormonal contraception and HIV acquisition,” he wrote.
UNAIDS has already called for more research and analysis before a January 2012 meeting when the World Health Organization (WHO) will review various studies as it prepares to revise recommendations on HIV and contraception use.
"If a new study is proposed, it will be years until we have the results so that's why it's important to have correct messaging," said Baeten, adding that women should continue to be offered hormonal contraception but that they should be counselled about the possible risks. The importance of condom use alongside other birth control should be re-enforced.
"This study should not result in women stopping contraception - it's too important from the individual and pubic health perspective," he told IRIN/PlusNews. "It should promote a conversation about how we keep women safe while reducing unplanned pregnancy and the complications from that."
Adapting family planning in Africa
With the WHO recommending family-planning services as the first step to reducing maternal mortality and deaths linked to botched abortion, several countries, including Nigeria, Uganda and South Africa, have recently rejuvenated such services to bring down their stubbornly high maternal mortality rates.
In Uganda, USAID recently announced the rollout of the birth control pill Mycrogynon following a similar 2010 campaign in Ethiopia.
South Africa is revising its family-planning guidelines and has embarked on a national campaign to increase access to contraception.
|If a new study is proposed, it will take years until we have results so that's why it's important to have correct messaging|
According to Eddie Mhlanga, cluster manager for maternal, child and woman health and nutrition in South Africa's Department of Health, the new family-planning guidelines will caution health workers about the increased risk of HIV associated with hormonal contraception.
The guidelines may also demonstrate a shift towards contraception with lower hormone levels, and the re-introduction of intrauterine contraceptive devices (IUCDs), Mhlanga told IRIN/PlusNews.
The last available data from 2003 showed South Africa's hardest-hit province, KwaZulu-Natal, had the highest uptake of contraception in the country, predominately hormone injections.
To address the over-reliance on injections, the province plans to expand access to birth-control pills, including emergency contraception, as well as condoms and IUCDs, which are inserted into the uterus in order to prevent pregnancy.
According to Baeten, non-hormonal IUCDs may be a good option for women in high HIV prevalence settings.
"From the point of a medical intervention, it would be about provider preferences and patient demand," he told IRIN/PlusNews. "Whether it’s a choice in contraception or a choice of soda, part of that is about what strategies are put in place to promote it."