2. Wildfire Exposure Characteristics of Cohort over Pregnancy and Individual Trimesters.

		pregnancy	1st trimester	2nd trimester	3rd trimester
wildfire PM2.5 concn (μg/m3)	mean (SD)	0.18 (0.21)	0.18 (0.38)	0.18 (0.36)	0.18 (0.39)
	median (IQR)	0.10 (0.21)	0.04 (0.15)	0.05 (0.16)	0.05 (0.16)
no. of wildfire smoke days	mean (SD)	9.55 (6.89)	3.14 (4.16)	3.42 (4.35)	2.99 (3.98)
	median (IQR)	8 (13)	1 (4)	2 (4)	1 (4)
no. of wildfire smoke days > 3 μg/m3	mean (SD)	4.83 (4.65)	1.60 (2.82)	1.71 (2.92)	1.52 (2.71)
	median (IQR)	3 (7)	0 (2)	0 (2)	0 (2)
no. of wildfire smoke days > 5 μg/m3	mean (SD)	2.78 (3.50)	0.93 (2.09)	0.99 (2.15)	0.87 (2.00)
	median (IQR)	1 (4)	0 (1)	0 (1)	0 (1)

^aWildfire PM_2.5 concentrations are averaged per individual across each period including non-wildfire days (where concentrations are 0 μg/m³).

^bNote that the number of smoke days is inclusive of the number of smoke days > 3 μg/m³ and > 5 μg/m³, as number of smoke days >3 μg/m³ are inclusive of number of smoke days >5 μg/m³.

^cSD, standard deviation.

^dIQR, interquartile range.