Predictors of stillbirth among HIV-infected Tanzanian women

Abstract

Objective: To determine maternal risk factors for stillbirth among pregnant HIV-infected women in sub-Saharan Africa. Design: Prospective cohort study nested within a micronutrient trial. At enrollment, maternal sociodemographic, obstetric, immunologic, clinical, and nutritional variables were measured. Women were followed through monthly clinic visits until delivery. Multivariate predictors of stillbirth were identified in Poisson regression models. Setting: Antenatal clinic in a tertiary care hospital in urban Dar es Salaam, Tanzania. Population: N = 1,078 women enrolled between 12 and 27 weeks of gestation. Main outcome measures: Stillbirth (delivery of dead baby ≥ 28 weeks’ gestation), fresh stillbirth, and macerated stillbirth. Results: Among 1,017 singleton pregnancies, there were 49 stillbirths, yielding a stillbirth risk of 50.0 per 1,000 deliveries (95% Confidence Interval(CI) = 37.2, 65.6). Of stillbirths with known type, 53.7% were fresh and 46.3% macerated. In multivariate analyses, baseline measures of late ( ≥ 21 weeks’ gestation) study entry (Relative Risk (RR) = 2.13, 95% CI = 1.17, 3.87), CD3 count ≥ 1,179 cells/ml (RR = 2.15, 95% CI = 1.16, 4.01), stillbirth history (RR = 3.53, 95% CI = 1.30, 9.59), primiparity (RR = 3.65, 95% CI = 1.83, 7.29), and syphilis infection (RR = 2.06, 95% CI = 1.09, 3.88) predicted increased stillbirth risk. Late study entry, illiteracy, stillbirth history, primiparity, CD3 count ≥ 1,179 cells/ml, gonorrhea infection, and previous hospitalization predicted increased risk of fresh stillbirth, while living alone and syphilis infection predicted increased risk of macerated stillbirth. Conclusions: Applying antenatal screening and preventive tools for the socioeconomic, obstetric, immunologic, and clinical risk factors identified may assist in reducing the high incidence of stillbirth among HIV-infected women in urban sub-Saharan Africa.