Migration and first-year maternal mortality among HIV-positive postpartum women: A population-based longitudinal study in rural South Africa

Abstract

Background

In South Africa, within-country migration is common. Mobility affects many of the factors in the pathway for entry to or retention in care among people living with HIV. We characterized the patterns of migration (i.e., change in residency) among peripartum women from rural South Africa and their association with first-year postpartum mortality.

Methods and findings

All pregnant women aged ≥15 years were followed-up during pregnancy and the first year postpartum in a population-based longitudinal demographic and HIV surveillance program in KwaZulu-Natal, South Africa, from 2000 to 2016. During the household surveys (every 4–6 months), each household head was interviewed to record demographic components of the household, including composition, migration, and mortality. External migration was defined as moving (i.e., change in residency) into or out of the study area. For women of reproductive age, detailed information on new pregnancy and birth was recorded. Maternal death was ascertained via verbal autopsy and HIV status at delivery via annual HIV surveys. We fitted mixed-effects Cox regression models adjusting for multiple pregnancies per individual. Overall, 19,334 women had 30,291 pregnancies: 3,339 were HIV-positive, 10,958 were HIV-negative, and 15,994 had unknown HIV status at delivery. The median age was 24 (interquartile range: 20–30) years. During pregnancy and the first year postpartum, 64% ( n = 19,344) and 13% ( n = 3,994) did not migrate and resided within and outside the surveillance area, respectively. Of the 23% who had externally migrated at least once, 39% delivered outside the surveillance area. Overall, the mortality rate was 5.8 per 1,000 person-years (or 831 deaths per 100,000 live births) in the first year postpartum. The major causes of deaths were AIDS- or tuberculosis-related conditions both within 42 days of delivery (53%) and during the first year postpartum (62%). In this study, we observed that HIV-positive peripartum women who externally migrated and delivered outside the surveillance area had a hazard of mortality more than two times greater (hazard ratio = 2.74; 95% confidence interval 1.01–7.40, p-value = 0.047)—after adjusting for age, time period (before or after 2010), and sociodemographic status—compared to that of HIV-positive women who continuously resided within the surveillance area. Study limitations include lack of data on access to antiretroviral therapy (ART) care and social or clinical context at the destinations among mobile participants, which could lead to unmeasured confounding. Further information on how mobile postpartum women access and remain in care would be instructive.

Conclusions

In this study, we found that a substantial portion of peripartum women moved within the country around the time of delivery and experienced a significantly higher risk of mortality. Despite the scale-up of universal ART and declining trends in maternal mortality, there is an urgent need to derive a greater understanding of the mechanisms underlying this finding and to develop targeted interventions for mobile HIV-positive peripartum women.

Abstract

In a study done in South Africa, Hae-Young Kim and colleagues investigate migration and maternal mortality in women with HIV infection.

Author summary

Why was this study done?

• Within-country migration is common among young women, often seeking economic or educational opportunities at nearby cities.

• Migration is a risk factor for poor retention in care among people living with HIV. HIV-positive women who initiate or continue lifelong antiretroviral therapy (ART) during pregnancy face unique challenges to remain in HIV care in the postpartum period, potentially leading to worse health outcomes.

• Little is known about within-country mobility patterns among peripartum women and their link to maternal health outcomes.

What did the researchers do and find?

• Using one of the largest population-based longitudinal HIV and demographic surveys (2000–2016), we characterized the patterns of external migration (i.e., change of residency into or away from the study area) among peripartum women from rural KwaZulu-Natal, South Africa, and examined the first-year risk of death by maternal HIV status and migration patterns.

• More than 20% had externally migrated at least once during pregnancy and in the first year postpartum; of these, about 40% delivered outside the study area. Overall, the maternal mortality rate was very high at 5.8 per 1,000 person-years (or 831 deaths per 100,000 live births) in the first year postpartum.

• HIV-positive peripartum women who externally migrated and delivered outside the study area had more than two times the hazard of mortality, compared to those who continuously resided within the surveillance area. However, such an association was not observed among HIV-negative peripartum women.

What do these findings mean?

• In this study in rural South Africa, we found that a substantial portion of peripartum women migrates around the time of delivery. Mobile HIV-positive peripartum women experience poor health outcomes, including higher first-year mortality.

• Further understanding of how mobile HIV-positive postpartum women access and remain in care is critical to provide targeted interventions and improve maternal health outcomes.