Effect of HIV infection on pregnancy-related mortality in sub-Saharan Africa: secondary analyses of pooled community-based data from the network for Analysing Longitudinal Population-based HIV/AIDS data on Africa (ALPHA)

Abstract

Background: Model-based estimates of the global proportions of maternal deaths that are in HIV-infected women range from 7% to 21%, and the effects of HIV on the risk of maternal death is highly uncertain. We used longitudinal data from the Analysing Longitudinal Population-based HIV/AIDS data on Africa (ALPHA) network to estimate the excess mortality associated with HIV during pregnancy and the post-partum period in sub-Saharan Africa.

Methods: The ALPHA network pooled data gathered between June, 1989 and April, 2012 in six community-based studies in eastern and southern Africa with HIV serological surveillance and verbal-autopsy reporting. Deaths occurring during pregnancy and up to 42 days post partum were defined as pregnancy related. Pregnant or post-partum person-years were calculated for HIV-infected and HIV-uninfected women, and HIV-infected to HIV-uninfected mortality rate ratios and HIV-attributable rates were compared between pregnant or post-partum women and women who were not pregnant or post partum.

Findings: 138,074 women aged 15-49 years contributed 636,213 person-years of observation. 49,568 women had 86,963 pregnancies. 6760 of these women died, 235 of them during pregnancy or the post-partum period. Mean prevalence of HIV infection across all person-years in the pooled data was 17.2% (95% CI 17.0-17.3), but 60 of 118 (50.8%) of the women of known HIV status who died during pregnancy or post partum were HIV infected. The mortality rate ratio of HIV-infected to HIV-uninfected women was 20.5 (18.9-22.4) in women who were not pregnant or post partum and 8.2 (5.7-11.8) in pregnant or post-partum women. Excess mortality attributable to HIV was 51.8 (47.8-53.8) per 1000 person-years in women who were not pregnant or post partum and 11.8 (8.4-15.3) per 1000 person-years in pregnant or post-partum women.

Interpretation: HIV-infected pregnant or post-partum women had around eight times higher mortality than did their HIV-uninfected counterparts. On the basis of this estimate, we predict that roughly 24% of deaths in pregnant or post-partum women are attributable to HIV in sub-Saharan Africa, suggesting that safe motherhood programmes should pay special attention to the needs of HIV-infected pregnant or post-partum women.

Funding: Wellcome Trust, Health Metrics Network (WHO).

Figure 1

Mortality rates in HIV-infected and HIV-uninfected women, by pregnancy status and availability of ART Pooled Analysing Longitudinal Population-based HIV/AIDS data on Africa (ALPHA) network data, 1990–2012. Bars are 95% CIs. ART=antiretroviral therapy. PPP=pregnant or post partum.

Figure 2

Proportion of pregnant or post-partum women infected with HIV at the time of their death of all deaths of pregnant or post-partum women with known HIV status, and mean prevalence of HIV infection in female population, by study site Estimate of prevalence in the study population aged 15–50 years based on person-years lived with known HIV status. PPP=pregnant or post partum.