[Retracted] Exposure to Ambient Air Pollutant PM₁₀ in the Second Trimester of Pregnancy Is Associated with Preterm Birth: A Birth-Based Health Information Cohort Study

Table 2

Crude and adjusted odd ratios for the risk of gestational age (wk) and PTB caused by PM₁₀ exposure in the second trimester of pregnancy.

Outcome	Crude		Model I		Model II
	OR/ (95% CI)	value	OR/ (95% CI)	value	OR/ (95% CI)	value
Gestational age (wk)
(μg/m^3)	0.02 (0.01, 0.02)	<0.001	0.02 (0.01, 0.03)	<0.001	0.02 (0.01, 0.03)	<0.001
(μg/m^3)	-0.47 (-0.48, -0.46)	<0.001	-0.48 (-0.50, -0.47)	<0.001	-0.48 (-0.49, -0.47)	<0.001
PTB
(μg/m^3)	1.02 (1.00, 1.04)	0.129	1.00 (0.95, 1.06)	0.883	1.01 (0.95, 1.05)	0.992
(μg/m^3)	1.71 (1.63, 1.78)	<0.001	1.75 (1.67, 1.83)	<0.001	1.78 (1.69, 1.87)	<0.001

OR: odds ratio; CI: confidence interval. Model I adjusted for season of conception and maternal age. Model II adjusted for season of conception, parity, maternal age, preeclampsia, history of cesarean section, maternal anemia, maternal obesity, and diabetes.