using injectable (hormonal) contraceptives had a significantly lower rate of
pregnancy compared to those using oral contraception in a major HIV prevention study, researchers report in the advance online edition of AIDS.
However, the same study also found that women who used an injectable hormonal contraceptive method were at higher risk of both acquiring and passing on HIV, indicating the dilemma posed for HIV prevention studies and the women who take part in them by the issue of contraception.
HIV-positive and negative women who used contraceptive pills were more than
twice as likely to become pregnant (aHR: 2.22, p=0.01 and aHR: 2.65, p=0.09,
respectively) than those who used injectable contraception.
results from this secondary analysis, of a prospective randomised double-blind
placebo controlled trial looking at the effect of herpes treatment on HIV
transmission, are in keeping with other studies showing injectable
contraception is more effective than oral contraception in reducing the
likelihood of pregnancy.
contraceptive use significantly reduced the risk of pregnancy among
HIV-positive women (aHR: 0.51, p=0.004) but not among HIV-negative women (aHR:
of pregnancy were high for both HIV-positive and HIV-negative women (incidence
15.6 and 14.8 per 100 woman-years, respectively). These rates are comparable to
other HIV prevention trials as well as in general in sub-Saharan Africa where an estimated one in four (25%) pregnancies
contraceptive use in clinical trials looking at new HIV prevention strategies
mean minimising protocol-required discontinuation of study products during
pregnancy and foetal exposure, note the authors. Recent HIV prevention trials,
they add, have required use of an effective contraceptive method to qualify for
However, previous previous secondary analyses from the
same study have suggested that injectable methods both double the risk of acquiring
as well as passing on HIV; and for a woman who is HIV-positive the risk for her
to pass on HIV when she is pregnant is also doubled. These analyses, however,
are observational, so are inconclusive; some studies support them while others
association between pregnancy and injectable contraception and HIV transmission
may relate to the higher dose of hormones compared to other hormonal
The question of which contraceptive method to use is also of
importance for women living with HIV who want to avoid pregnancy. Reducing unwanted pregnancies in women living with HIV is one of the four pillars of the global
strategy for prevention of mother-to-child transmission of HIV, yet people living with HIV in sub-Saharan Africa have high levels of unmet need regarding contraceptive advice and supplies.
Reducing unintended pregnancy might also be expected to have an effect on onward transmission of HIV. The Partners in Prevention study also found that pregnancy in women living with HIV doubled the risk of female-to-male HIV transmission.
authors note that factors identified by other studies as affecting pregnancy rates among
African women included younger age, fewer children, living with a male partner
and having frequent sex without using condoms.
few have looked at whether the choice of contraceptive method has an effect
upon the incidence of pregnancy in HIV-negative and HIV-positive African women.
December 2004 and October 2008, 3408 heterosexual HIV serodiscordant couples
were enrolled in the Partners in Prevention HSV/HIV transmission study
conducted in 14 sites in seven countries in East and Southern Africa (Botswana,
Kenya, Rwanda, South Africa, Tanzania, Uganda and Zambia. The herpes treatment,
aciclovir, had no effect on HIV transmission. The authors chose to do a
secondary analysis of the findings to determine pregnancy incidence according
to the contraceptive method used. (Contraceptive method was not randomly assigned.)
the 3354 women - of whom approximately two-thirds were HIV positive and one
third HIV negative - the median age was 30. Women had an average of one to two
children and reported four (IQR:2-8) sex acts each month. The median follow-up
was 1.64 (IQR: 1.21-1.97) and 1.68 (IQR: 1.25-2.00) years for HIV-positive and
HIV-negative women, respectively.
the very few women using intrauterine devices (IUDs) and implanted
contraception, both non-hormonal methods, none became pregnant. These findings
add to other reports showing IUD use to be safe and effective in preventing
pregnancy among women at risk for HIV, yet its use in sub-Saharan Africa remains very low, note the authors.
data provide additional evidence of the potential for safe and effective
long-acting user-independent contraceptive methods to reduce unintended
pregnancies among HIV-negative and positive African women.”
who relied on their partners to use condoms as the primary contraceptive method
in the relationship were around three times more likely to become pregnant than
women who used an injectable contraceptive (aHR: 3.39, p<0.001 and aHR:
authors point to qualitative work they have done with serodiscordant couples
noting the challenges of consistent and correct condom use, notably for
conclude: “Family planning programmes and HIV prevention trials need innovative
way to motivate uptake and sustained use of longer acting less user-dependent
contraception for women with or at risk of HIV who do not desire pregnancy and
ensure that couples understand the importance of using dual methods for HIV and