Association between maternal HIV infection and the risks of preterm birth and low birth weight in Chengdu, China: a propensity score matching approach

OBJECTIVES: To estimate the effect of HIV infection on the risk of preterm birth (PTB) and low birth weight (LBW) among Chinese pregnancy women. DESIGN: A retrospective cohort study included HIV-positive pregnant women who gave birth to singletons in Chengdu between 2011 and 2020 and and HIV-negative pregnant women who delivered singletons at the Chengdu Women’s and Children’s Central Hospital in 2020. SETTING: Data of pregnant women living with HIV were extracted from China’s Information System of Prevention of Mother-to-Child Transmission of HIV Management. Additionally, information for HIV-negative pregnant women was extracted from the electronic medical record system of the Chengdu Women’s and Children’s Central Hospital. PARTICIPANTS: 755 HIV-positive women and 15,094 HIV-negative pregnant women were included. PRIMARY OUTCOME MEASURES: PTB and LBW rates, which were defined by gestational weeks and birth weight. RESULTS: The incidences of PTB and LBW (13.51% and 14.17%, respectively) were significantly higher in the HIV-positive group compared with the HIV-negative group (6.82% and 4.65%). Propensity score matching was performed to improve comparability of the two groups, resulting in 1590 pregnancies with 558 HIV-positive and 1032 HIV-negative women in the final analysis. Conditional logistic regression was used to estimate the effect of maternal HIV status on adverse pregnancy outcomes. After propensity score matching and controlling the potential confounders, HIV infection was strongly associated with higher chances of LBW and PTB with adjusted odd ratios (95% confidence interval) of 2.53 (1.74 to 3.68) and 1.95 (1.33 to 2.85), respectively. CONCLUSIONS: HIV infection was significantly associated with increased risks of PTB and LBW in Chinese pregnant women. Future studies should focus on investigating the mechanisms underlying the association between HIV infection and adverse birth outcomes, and on identifying strategies to reduce the incidence of PTB and LBW in pregnant women living with HIV.