Increased risk of HIV-1 transmission in pregnancy: a prospective study among African HIV-1 serodiscordant couples.

Publication Type:

Journal Article

Source:

AIDS (London, England), Volume 25, Issue 15, p.1887-1895 (2011)

Keywords:

2011, Adult, Africa South of the Sahara, Antibodies, Viral, Center-Authored Paper, Confidence Intervals, Female, Health Knowledge, Attitudes, Practice, HIV Seropositivity, HIV-1, Humans, Incidence, Male, Odds Ratio, PREGNANCY, Pregnancy Complications, Infectious, Prospective Studies, September 2011, Sexual Behavior, Sexual Partners, Vaccine and Infectious Disease Division

Abstract:

BACKGROUND:: Physiologic and behavioral changes during pregnancy may alter HIV-1 susceptibility and infectiousness. Prospective studies exploring pregnancy and HIV-1 acquisition risk in women have found inconsistent results. No study has explored the effect of pregnancy on HIV-1 transmission risk from HIV-1 infected women to male partners. METHODS:: In a prospective study of African HIV-1 serodiscordant couples, we evaluated the relationship between pregnancy and the risk of 1) HIV-1 acquisition among women and 2) HIV-1 transmission from women to men. RESULTS:: 3321 HIV-1 serodiscordant couples were enrolled, 1085 (32.7%) with HIV-1 susceptible female partners and 2236 (67.3%) with susceptible male partners. HIV-1 incidence in women was 7.35 versus 3.01 per 100 person-years during pregnant and nonpregnant periods (hazard ratio [HR] 2.34, 95% confidence interval [CI] 1.33-4.09). This effect was attenuated and not statistically significant after adjusting for sexual behavior and other confounding factors (adjusted HR 1.71, 95% CI 0.93-3.12). HIV-1 incidence in male partners of infected women was 3.46 versus 1.58 per 100 person-years when their partners were pregnant versus not pregnant (HR 2.31, 95% CI 1.22-4.39). This effect was not attenuated in adjusted analysis (adjusted HR 2.47, 95% CI 1.26-4.85). CONCLUSIONS:: HIV-1 risk increased two-fold during pregnancy. Elevated risk of HIV-1 acquisition in pregnant women appeared in part to be explained by behavioral and other factors. This is the first study to show pregnancy increased the risk of female-to-male HIV-1 transmission, which may reflect biological changes of pregnancy that could increase HIV-1 infectiousness.