Objective: To determine the incidence of HIV during pregnancy as defined by seroconversion using a repeat HIV rapid testing strategy during late pregnancy.
Design: Cross-sectional study nested in a prevention of mother-to-child transmission program
Methods: Pregnant women were retested between 36 and 40 weeks of gestation, provided that they had been tested HIV negative at least 3 months prior.
Results: Among the 2377 HIV-negative women retested, 1099 (46.2%) and 1278 (53.4%) were tested at urban and rural health facilities, respectively. Seventy-two women (3%) were HIV-positive (679 woman years of exposure) yielding a HIV incidence rate of 10.7/100 woman years [95% confidence interval (CI) 8.2-13.1]. HIV incidence in pregnancy was higher but not statistically significant at the urban facilities (12.4/100 woman years versus 9.1/100 woman years) and at least two-fold higher among the 25-29 and 30-34-year age groups (3.8 and 4.5%, respectively) as compared with the less than 20-year age group (1.9%). Single women were at 2.5 times higher risk of seroconverting during pregnancy (P = 0.017).
Conclusion: HIV incidence during pregnancy is four times higher than in the nonpregnant population reported in a recent survey. Public health programs need to continue to reinforce prevention strategies and HIV retesting during pregnancy. The latter also offers an additional opportunity to prevent mother-to-child transmission and further horizontal transmission. Further research is required to understand the cause of primary HIV infection in pregnancy.