Associations of Ambient Particulate Matter with Maternal Thyroid Autoimmunity and Thyroid Function in Early Pregnancy
Enjie Zhang, Zheng Zhang, Gongbo Chen, Yunting Zhang, Shaofei Su, Shen Gao, Shuanghua Xie, Jianhui Liu, Yue Zhang, Wentao Yue, Qingqing Wu, Yi Chen, Bo‐Yi Yang, Yuming Guo, Ruixia Liu, Guang‐Hui Dong, Chenghong Yin
Abstract
High Resolution Image Download MS PowerPoint Slide This prospective birth cohort study evaluated the association of exposure to PM 2.5 (diameter ≤2.5 μm), PM 1–2.5 (1–2.5 μm), and PM 1 (≤1 μm) with maternal thyroid autoimmunity and function during early pregnancy. A total of 15,664 pregnant women were included at 6 to 13 +6 gestation weeks in China from 2018 to 2020. Single-pollutant models using generalized linear models (GLMs) showed that each 10 μg/m 3 increase in PM 2.5 and PM 1–2.5 was related with 6% (odds ratio [OR] = 1.06, 95% confidence interval [CI]: 1.01, 1.12) and 15% (OR = 1.15, 95% CI: 1.08, 1.22) increases in the risk of thyroid autoimmunity, respectively. The odds of thyroid autoimmunity significantly increased with each interquartile range increase in PM 2.5 and PM 1–2.5 exposure ( P for trend <0.001). PM 1 exposure was not significantly associated with thyroid autoimmunity. GLM with natural cubic splines demonstrated that increases in PM 2.5 and PM 1–2.5 exposure were associated with lower maternal FT4 levels, while a negative association between PM 1 and FT4 levels was found when exposure exceeded 32.13 μg/m 3 . Only PM 2.5 exposure was positively associated with thyrotropin (TSH) levels. Our findings suggest that high PM exposure is associated with maternal thyroid disruption during the early pregnancy.