Objective: Several studies have suggested that pregnancy is associated with an increased risk of HIV-1 acquisition. We used data from a large, prospective study of hormonal contraception and HIV-1 to evaluate the effect of pregnancy on the risk of HIV-1 acquisition.
Design: A multicenter prospective cohort study.
Methods: We examined 4439 women from family planning sites in Uganda and Zimbabwe contributing 31 369 follow-up visits during 1999–2004. Participants were aged 18–35 years, and had received pregnancy and HIV-1 testing quarterly for 15–24 months. Using proportional hazards modeling, we compared the time to HIV-1 acquisition among four groups: pregnant women, non-pregnant lactating (NP/L) women, and women neither pregnant nor lactating (NP/NL) who were either using or not using hormonal contraception.
Results: A total of 211 participants became HIV-1 infected (2.7 per 100 woman-years; wy), including 13 pregnant women (1.6 per 100 wy), 33 NP/L women (2.7 per 100 wy), 126 NP/NL women using hormonal contraception (2.9 per 100 wy), and 39 NP/NL women not using hormonal contraception (2.7 per 100 wy). In multivariable analysis adjusting for site, age, living with partner, risky sexual behaviors, and incident vaginal, cervical and herpes simplex virus 2 infections, neither pregnant, NP/L, nor NP/NL women using hormonal contraception were at an increased risk of HIV-1 acquisition compared with NP/NL women not using hormonal contraception.
Conclusion: Neither pregnancy nor lactation placed women at increased risk of HIV-1 acquisition in this multisite, prospective study of African women. This information is important in planning interventions to reduce HIV-1 acquisition among women.
From the aClinical Research Department, Family Health International, Research Triangle Park, North Carolina, USA
bStatistical Center for HIV/AIDS Research and Prevention (SCHARP), Fred Hutchinson Cancer Research Center, Seattle, Washington, USA
cDivision of Infectious Diseases, Indiana University School of Medicine, Indianapolis, Indiana, USA
dDepartment of Obstetrics, Gynecology and Reproductive Sciences, University of California at San Francisco, San Francisco, California, USA
eDepartment of Medicine, Case Western Reserve University, Cleveland, Ohio, USA
fDepartment of Biostatistics, University of Washington, Seattle, Washington, USA.
Received 30 October, 2006
Revised 15 January, 2007
Accepted 30 January, 2007
Correspondence to Charles S. Morrison, PhD, Family Health International, PO Box 13950, Research Triangle Park, NC, 27709, USA. Tel: +1 919 544 7040; fax: +1 919 544 7261; e-mail: email@example.com