Table 2.

ORs for gestational diabetes in relation to NO_x (µg/m³) and traffic density (vehicles/min).

Exposure	Crude OR (95% CI)	Adjusted OR (95% CI)
NOx quartile
Q1 = 2.5–8.9	1.00 (reference)	1.00 (reference)
Q2 = 9.0–14.1	1.28 (1.07, 1.54)	1.19 (0.99, 1.44)
Q3 = 14.2–22.6	1.84 (1.56, 2.18)	1.52 (1.28, 1.82)
Q4 = > 22.7	1.98 (1.68, 2.35)	1.69 (1.41, 2.03)
Traffic density within 200 m
No road	1.00 (reference)	1.00 (reference)
< 2	0.89 (0.75, 1.06)	0.93 (0.78, 1.12)
2–5	1.04 (0.88, 1.23)	0.96 (0.81, 1.14)
5–10	1.53 (1.27, 1.84)	1.18 (0.97, 1.43)
> 10	1.50 (1.24, 1.82)	1.23 (1.01, 1.51)
Gestational diabetes model adjusted for parity, BMI, maternal age, calendar year, and country of origin and exposure for second trimester.