Increased Risk of HIV Acquisition Among Women Throughout Pregnancy and During the Postpartum Period: A Prospective Per-Coital-Act Analysis Among Women With HIV-Infected Partners

Kerry A Thomson, James Hughes, Jared M Baeten, Grace John-Stewart, Connie Celum, Craig R Cohen, Kenneth Ngure, James Kiarie, Nelly Mugo, Renee Heffron

Understanding the absolute and relative risk of human immunodeficiency virus type 1 (HIV) acquisition during pregnancy and the postpartum period can inform HIV prevention strategies for women.

We used a complementary log-log model and data from 2751 HIV-serodiscordant couples to compare the probability of HIV acquisition among women per sex act during early pregnancy, late pregnancy, the postpartum period, and the nonpregnant period.

At total of 686 pregnancies were identified, and 82 incident HIV infections occurred. After adjustment for condom use, age, preexposure prophylaxis (PrEP) use, and HIV viral load, the per-act probability of HIV acquisition was higher in late pregnancy (adjusted relative risk [aRR], 2.82; P = .01) and the postpartum period (aRR, 3.97; P = .01) as compared to that during nonpregnant period. For a 25-year-old woman not taking PrEP, the HIV acquisition probability per condomless sex act with an HIV-infected male partner with a viral load of 10 000 copies/mL was 0.0011 (95% confidence interval [CI] 0.005–0.0019), 0.0022 (95% CI, 0.0004–0.0093), 0.0030 (95% CI, 0.0007–0.0108), and 0.0042 (95% CI, 0.0007–0.0177) during the nonpregnant period, early pregnancy, late pregnancy, and the postpartum period, respectively.

The HIV acquisition probability per condomless sex act steadily increased during pregnancy and was highest during the postpartum period, suggesting that biological changes during pregnancy and the postpartum period increase HIV susceptibility among women.


July 31, 2018
Year of publication
Resource types
Journal and research articles
HIV acquisition risks, condomless sex, HIV prevention strategies, HIV-seroconversion during pregnancy (HSP), pregnancy, postpartum, HIV susceptibility

Similar Resources

HIV acquisition during pregnancy and breastfeeding significantly contributes toward paediatric HIV infection; however, little is known about risk behaviours in HIV-uninfected pregnant and postpartum women.

Many countries are working to reduce or eliminate mother-to-child transmission (MTCT) of HIV. Prevention efforts have been conceptualized as steps in a cascade but cascade completion rates during and after pregnancy are low.

This paper documents the development of the global and national monitoring and reporting systems for PMTCT and paediatric HIV care and treatment programmes, achievements and remaining challenges.

To understand the uptake of HIV services by adolescent women, the authors conducted a retrospective analysis of patient-level data (2011–2013) on services for antenatal care (ANC) and prevention of mother-to-child transmission (PMTCT) in 36 facilities in 5 districts in Zimbabwe.

In 2013, Uganda updated its prevention of maternal-to-child transmission of HIV program to Option B+, which requires that all HIV-infected pregnant and breastfeeding women be started on lifelong antiretroviral therapy (ART) regardless of CD4 count…

This article is featured in the SHARE Research Digest. Click here to learn more.

We conducted a retrospective study to investigate the effectiveness of an mHealth messaging intervention aiming to improve maternal health and HIV outcomes.

Option B+ for prevention of mother-to-child transmission (PMTCT) specifies treating all HIV-positive women with antiretroviral therapy (ART) regardless of CD4 count. This simplified approach enhances countries' capacity to reach national HIV targets and contribute to the global 90-90-90 goals.…

This study aimed to evaluate the impact of clinic-based prevention of mother-to-child transmission (PMTCT) community support by trained lay health workers in addition to standard clinical care on PMTCT infant outcomes.

An essential first step in caring for HIV-infected children is accurate and early diagnosis of HIV, early HIV testing, prompt return of results, and rapid initiation of treatment.