Prenatal exposure to fine particulate matter chemical constituents and the risk of stillbirth and the mediating role of pregnancy complications: A cohort study

Tianshan Shi; Hanping Ma; Donghua Li; Li Pan; Tingrong Wang; Rui Li; Xiaowei Ren

doi:10.1016/j.chemosphere.2023.140858

Prenatal exposure to fine particulate matter chemical constituents and the risk of stillbirth and the mediating role of pregnancy complications: A cohort study

Chemosphere. 2024 Feb:349:140858. doi: 10.1016/j.chemosphere.2023.140858. Epub 2023 Dec 2.

Authors

Tianshan Shi¹, Hanping Ma², Donghua Li¹, Li Pan², Tingrong Wang¹, Rui Li¹, Xiaowei Ren³

Affiliations

¹ Institute of Epidemiology and Health Statistics, School of Public Health, Lanzhou University, Lanzhou, Gansu, 730000, China.
² Lanzhou Maternal and Child Health Hospital, Lanzhou, Gansu, 730000, China.
³ Institute of Epidemiology and Health Statistics, School of Public Health, Lanzhou University, Lanzhou, Gansu, 730000, China. Electronic address: renxw@lzu.edu.cn.

PMID: 38048830
DOI: 10.1016/j.chemosphere.2023.140858

Abstract

Evidence on the association of fine particulate matter (PM_2.5) exposure with stillbirth is limited and inconsistent, which is largely attributed to differences in PM_2.5 constituents. Studies have found that the hazards of certain PM_2.5 constituents to the fetus are comparable to or even higher than total PM_2.5 mass. However, few studies have linked PM_2.5 constituents to stillbirth. Moreover, the mediating role of pregnancy complications in PM_2.5-related stillbirth remains unclear. To our knowledge, this study was the first to explore the individual and mixed associations of PM_2.5 and its constituents with stillbirth in China. After matching the concentrations of PM_2.5 and its constituents (sulfate [SO₄^2-], nitrate [NO₃^-], ammonium [NH₄⁺], organic matter [OM], and black carbon [BC]) for participants according to their geographical location, there were 170,507 participants included in this study. We found that stillbirth was associated with exposure to PM_2.5 and its constituents in the year before pregnancy and during the entire pregnancy, and the associations in trimester 1 were strongest. The risk of stillbirth increased sharply when PM_2.5 and its constituents during pregnancy exceeded the median concentrations. Moreover, stillbirth was associated with exposure to the mixtures of SO₄^2-, NO₃^-, NH₄⁺, OM, and BC before and during pregnancy (trimesters 1 and 2). Meanwhile, two-pollutant models also suggested stillbirth was associated with PM_2.5 and its constituents in the year before and during pregnancy. The associations of PM_2.5 and its constituents with stillbirth were stronger in mothers with advanced age and without cesarean delivery history. Additionally, hypertensive disorders in pregnancy, gestational diabetes, and placental abruption mediated the association of PM_2.5 with stillbirth. Therefore, enhanced protection against PM_2.5 for pregnant women before and during pregnancy and targeted interventions for pregnancy complications and anthropogenic sources of PM_2.5 constituents are important to reduce stillbirth risk.

Keywords: Mediating role; PM(2.5) constituents; Pregnancy complications; Stillbirth.

MeSH terms

Air Pollutants* / toxicity
Air Pollution* / adverse effects
Air Pollution* / analysis
China
Cohort Studies
Environmental Exposure
Female
Humans
Maternal Exposure / adverse effects
Particulate Matter / analysis
Placenta / chemistry
Pregnancy
Prenatal Exposure Delayed Effects*
Stillbirth / epidemiology

Substances

Particulate Matter
Air Pollutants