Association between Maternal Exposure to Arsenic during Pregnancy and Risk of Preterm Birth: A Systematic Review and Meta-Analysis

Several observational studies have suggested that maternal exposure during pregnancy to arsenic is associated with the risk of preterm birth (PTB); however, available evidence is inconsistent. Therefore, we aimed to explore the relation of maternal exposure to arsenic to PTB risk.

A comprehensive systematic search was carried out from inception to April 2023 in PubMed and Scopus to retrieve all relevant studies. A pooled odds ratio (OR) with corresponding 95% confidence interval (CI) was employed using a random effects model to test the association.

As a result, 14 eligible studies, with 12,619 participants, were included in the meta-analysis. Overall, the pooled OR of all analyzed studies indicated that higher maternal arsenic exposure is significantly related to the 1.12-fold increased odds of PTB (OR = 1.12, 95% CI = 1.04-1.21), with a remarkable heterogeneity across studies (P = <0.001, I2 = 70.9%). This association was found in prospective cohort studies (OR = 1.15, 95% CI = 1.05-1.26), but not in non-cohort studies. In the stratified analysis, the majority of subgroups supported the association of arsenic with PTB.

Maternal exposure to arsenic during pregnancy is directly linked to the odds of PTB. Future studies are suggested to investigate the effectiveness of specific measures to decrease exposure to arsenic in high-risk communities, particularly in pregnant women.