Preterm delivery risk in relation to maternal HIV infection, history of malaria and other infections among urban Zimbabwean women.

OBJECTIVE To examine preterm delivery risk in relation to maternal HIV infection, malaria history, and other infections among Zimbabwean women. DESIGN Hospital based, cross sectional study. SETTING Harare Maternity Hospital, Harare, Zimbabwe. SUBJECTS A convenient sample of 500 pregnant women. MAIN OUTCOME MEASURE Preterm delivery. THE STUDY FACTORS: Maternal socio-demographic information, and infectious disease history (during the year before pregnancy). METHOD Between July 1998 and March 1999 data were collected for a cross sectional study of pregnant women who delivered at the Harare Maternal Hospital. The association of maternal HIV infection, history of malaria, and other infections with preterm delivery were determined using multivariate analysis. RESULTS Overall, 497 women were studied, 444 (89.3%) delivered at term and 53 women (10.7%) delivered preterm. Women who delivered preterm were less likely to be HIV seropositive compared with others (odds ratio [OR] = 0.75. 95% confidence interval (CI): 0.38 to 21.48). Preterm delivery was associated with having tuberculosis infections in the year prior to the pregnancy (OR = 10.15, 95% CI: 1.15 to 89.87). Other infections associated with preterm delivery were malaria (OR = 2.39, 95% CI: 1.07 to 5.31), chest infections (OR = 2.63, 95% CI: 0.76 to 9.17), and Herpes (shingles) infection (OR = 2.58, 95% CI: 0.56 to 11.85). Overall, a positive history of any of the non-sexually transmitted infections (in aggregate) was associated with a 3.20 fold increase risk for preterm delivery (OR = 3.20. 95% CI: 1.59 to 6.43). Women with a history of infection and who did not use iron supplements during pregnancy, compared with women without such an history and who used iron supplements, experienced the highest risk for preterm delivery (OR = 8.34, 95% CI: 3.30 to 21.07). CONCLUSION Maternal non-STD infections, (i.e., tuberculosis, malaria, and chest infections) occurring in the year prior to pregnancy were associated with an increased risk of preterm delivery. The association of non-sexually transmitted infections and preterm delivery was particularly strong among women who did not use iron supplements during pregnancy.