Increased risk of HIV transmission in serodiscordant couples wishing to conceive

This article is more than 15 years old. Click here for more recent articles on this topic

Harm reduction interventions to avoid HIV transmission in heterosexual, serodiscordant couples who wish to have children are urgently needed, according to Dr Sara Brubaker, from Kenya, as reported at the Fifth IAS Conference on HIV Pathogenesis, Treatment and Prevention in Cape Town.

A study conducted in Kisumu, Kenya, found that HIV-serodiscordant couples, where one partner is HIV-infected and the other is not, continue to conceive despite knowledge of their serostatus. In this cohort, couples who conceived were at 80% increased risk of HIV transmission between the partners.

A large proportion of new HIV infections in sub-Saharan Africa occur in stable heterosexual partnerships.The Kenya AIDS Indicator Survey of 2007 showed that half of HIV-infected Kenyans have partners who are HIV-uninfected.



A serodiscordant couple is one in which one partner has HIV and the other has not. Many people dislike this word as it implies disagreement or conflict. Alternative terms include mixed status, magnetic or serodifferent.


The presence or absence of detectable antibodies against an infectious agent, such as HIV, in the blood. Often used as a synonym for HIV status: seronegative or seropositive.


A serodiscordant couple is one in which one partner has HIV and the other has not. Many people dislike this word as it implies disagreement or conflict. Alternative terms include mixed status, magnetic or serodifferent.

post-exposure prophylaxis (PEP)

A month-long course of antiretroviral medicines taken after exposure or possible exposure to HIV, to reduce the risk of acquiring HIV.

harm reduction

Harm reduction is a set of practical strategies and ideas aimed at reducing negative consequences associated with drug use (including safer use, managed use and abstinence). It is also a movement for social justice built on a belief in, and respect for, the rights of people who use drugs.

Prevention efforts have focused on couples-based HIV testing. Although couples studies in central Africa have shown that condom use increases when couples learn about their discordant status, these same studies had shown that 20 to 43% of couples continue to have unprotected intercourse despite knowledge of their serostatus. This behaviour is often motivated by the desire to have children.

A systematic review of factors influencing fertility desires in HIV-infected people showed the factors that positively influence the desire and intention to have children are young age, having few or no previous children and having access to antiretroviral treatment (ART).

Five hundred and thirty-two heterosexual HIV-serodiscordant couples were enrolled in the study. Forty-one (7.6%) of the HIV-uninfected partners seroconverted, at a rate of 4.6 per 100 person years. In 328 (61.7%) of the couples, the female was HIV-infected, compared to 204 (38.3%) where the male was HIV-infected. 95.3% of study participants were married to their partner.

There were 373 pregnancies during the study period (this number included men if their partner conceived) compared to 698 individuals who did not become pregnant.

A comparison of those who conceived and those who did not showed that 10.8% of individuals who conceived or whose partner conceived aquired HIV, compared to only 5.9% in those where no pregnancy occurred.

The relative risk of a partner aquiring HIV was 1.8 times greater in serodiscordant couples where pregnancy did not occur than in those where pregnancy did occur.

Individuals who conceived were significantly younger with a median age of 27 compared to 34 in those who did not become pregnant (p

The study investigators could not assess intentionality or if the pregnancies were unplanned. Researchers suggested that rather than people acquiring HIV while attempting to become pregnant, they may acquire HIV because of possible increased susceptibility to HIV due to pregnancy.

An analysis of timing of pregnancy in relation to seroconversion showed that approximately 30% of seroconversions occurred six months before conception, 35% in the six months after conception and the remaining 35% were remote from conception.

A second study in Kenya, carried out among a cohort of 296 stable, HIV-discordant couples at Kenyatta National Hospital in Nairobi, already participating in a study of immune responses in exposed but uninfected partners, found a one-year cumulative pregnancy rate of 10.5%, with no difference in pregnancy rates between HIV-positive and uninfected women. This study did not evaluate HIV incidence.

The study found a particularly high rate of pregnancy in women below the age of 30 who wanted children: after 500 days of follow-up, 30% of this group had become pregnant, compared with fewer than 5% of women under 30 who did not want children. Women in the earlier stages of relationships were significantly more likely to become pregnant, with the incidence of pregnancy falling by 16% for each year the couple had been together by the time of recruitment to the study.

Implications for service delivery

Despite being unable to assess intentionality for pregnancy in the first cohort, if a portion of these pregnancies were intentional, these couples were risking HIV transmission in order to conceive. In high-income settings there are high-tech interventions such as sperm washing available that make conception for serodiscordant couples safe. However, even in free-at-the-point-of-care health systems like the United Kingdom, assisted conception procedures like sperm washing are charged for.

Antiretroviral treatment may also reduce the risk of transmission when it is fully suppressive, and some clinics, particularly in Switzerland and the United Kingdom, have already begun counselling couples about how to time unprotected intercourse in order to maximise the potential for conception once undetectable viral load has been achieved on treatment.They may also offer antiretroviral drugs to the uninfected partner as pre- and post-exposure prophylaxis, an approach to managing conception that would be feasible and affordable in settings where it is possible to measure viral load and provide results promptly.

Interventions and public health campaigns addressing the desire to have children in serodiscordant couples need to be designed and implemented in low-income settings in order to address this issue. As researchers from the University of Washington and Kenyatta National Hospital norte, it is not enough to say “avoid unprotected sex”.

Further information

A powerpoint presentation by Sara Brubaker and a webcast of the conference session in which it was presented are available on the IAS 2009 website.