Effects of Particulate Matter on the Risk of Gestational Hypertensive Disorders and Their Progression

[Image: see text] Associations between particulate matter (PM) and gestational hypertensive disorders (GHDs) are well documented, but there is no evidence on the associations between PM and GHD progression, especially among those with assisted reproductive technology (ART) conceptions. To explore the effects of PM on the risk of GHDs and their progression among pregnant women with natural or ART conception, we enrolled 185,140 pregnant women during 2014–2020 in Shanghai and estimated the associations during different periods using multivariate logistic regression. During the 3 months of preconception, 10 μg/m(3) increases in PM concentrations were associated with increased risks of gestational hypertension (GH) (PM(2.5): aOR = 1.076, 95% CI: 1.034–1.120; PM(10): aOR = 1.042, 95% CI: 1.006–1.079) and preeclampsia (PM(2.5): aOR = 1.064, 95% CI: 1.008–1.122; PM(10): aOR = 1.048, 95% CI: 1.006–1.092 ) among women with natural conception. Furthermore, for women with ART conceptions who suffered current GHD, 10 μg/m(3) increases in PM concentrations in the third trimester elevated the risk of progression (PM(2.5): aOR = 1.156, 95% CI: 1.022–1.306 ; PM(10): aOR = 1.134, 95% CI: 1.013–1.270). In summary, women with natural conception should avoid preconceptional PM exposure to protect themselves from GH and preeclampsia. For women with ART conceptions suffering from GHD, it is necessary to avoid PM exposure in late pregnancy to prevent the disease from progressing.