Table 3 Relative risks for term low birth weight according to trimester-specific exposure to air pollutants.

25 – 50^th percentile

1.15 (0.89, 1.50)

1.16 (0.88, 1.53)

1.11 (0.83, 1.47)

51 – 75^th percentile

1.11 (0.85, 1.45)

1.04 (0.79, 1.37)

1.02 (0.77, 1.36)

> 75^th percentile

1.06 (1.80, 1.40)

1.01 (0.75, 1.35)

1.00 (0.74, 1.34)

Continuous****

1.01 (0.90, 1.14)

0.98 (0.86, 1.11)

0.98 (0.86, 1.12)

25 – 50^th percentile

0.93 (0.71, 1.22)

0.96 (0.73, 1.28)

0.98 (0.74, 1.31)

51 – 75^th percentile

1.15 (0.87, 1.52)

1.18 (0.88, 1.58)

1.12 (0.84, 1.50)

> 75^th percentile

1.30 (1.00, 1.67)

1.36 (1.04, 1.78)

1.26 (0.96, 1.66)

Continuous****

1.17 (1.02, 1.33)

1.20 (1.05, 1.38)

1.15 (1.00, 1.31)

25 – 50^th percentile

1.24 (0.95, 1.62)

1.24 (0.94, 1.64)

1.14 (0.86, 1.52)

51 – 75^th percentile

1.25 (0.96, 1.62)

1.24 (0.95, 1.64)

1.08 (0.82, 1.44)

> 75^th percentile

1.28 (1.00, 1.65)

1.33 (1.02, 1.74)

1.11 (0.84, 1.48)

Continuous****

1.09 (1.00, 1.18)

1.09 (1.00, 1.19)

1.03 (0.94, 1.14)

25 – 50^th percentile

0.99 (0.76, 1.30)

0.93 (0.70, 1.23)

0.90 (0.67, 1.20)

51 – 75^th percentile

1.13 (0.87, 1.45)

1.07 (0.82, 1.40)

1.07 (0.81, 1.41)

> 75^th percentile

1.01 (0.76, 1.33)

0.98 (0.73, 1.31)

0.98 (0.73, 1.30)

Continuous****

1.03 (0.92, 1.17)

1.03 (0.91, 1.18)

1.04 (0.91, 1.18)

25 – 50^th percentile

1.14 (0.89, 1.47)

1.12 (0.86, 1.46)

1.14 (0.88, 1.49)

51 – 75^th percentile

1.05 (0.80, 1.37)

1.13 (0.85, 1.50)

1.09 (0.82, 1.45)

> 75^th percentile

0.92 (0.71, 1.20)

1.04 (0.79, 1.37)

0.99 (0.75, 1.32)

Continuous****

0.93 (0.82, 1.05)

0.99 (0.87, 1.13)

0.97 (0.85, 1.11)

25 – 50^th percentile

0.98 (0.76, 1.28)

1.02 (0.77, 1.34)

0.99 (0.75, 1.31)

51 – 75^th percentile

1.09 (0.84, 1.40)

1.16 (0.89, 1.51)

1.10 (0.84, 1.45)

> 75^th percentile

1.00 (0.77, 1.28)

1.09 (0.83, 1.42)

1.01 (0.76, 1.34)

Continuous****

1.00 (0.91, 1.09)

1.02 (0.93, 1.12)

1.00 (0.90, 1.10)

25 – 50^th percentile

0.85 (0.64, 1.13)

0.89 (0.66, 1.19)

0.86 (0.64, 1.16)

51 – 75^th percentile

0.94 (0.72, 1.22)

0.95 (0.72, 1.25)

0.94 (0.71, 1.25)

> 75^th percentile

0.89 (0.67, 1.18)

1.01 (0.75, 1.36)

1.03 (0.76, 1.38)

Continuous****

0.94 (0.83, 1.07)

1.00 (0.87, 1.15)

1.01 (0.88, 1.16)

25 – 50^th percentile

1.05 (0.82, 1.34)

1.04 (0.80, 1.34)

1.03 (0.80, 1.34)

51 – 75^th percentile

0.80 (0.60, 1.07)

0.85 (0.63, 1.15)

0.81 (0.60, 1.10)

> 75^th percentile

0.87 (0.68, 1.13)

0.88 (0.67, 1.15)

0.82 (0.63, 1.08)

Continuous****

0.91 (0.80, 1.03)

0.93 (0.81, 1.06)

0.89 (0.78, 1.02)

25 – 50^th percentile

0.93 (0.72, 1.20)

0.96 (0.73, 1.26)

0.92 (0.70, 1.21)

51 – 75^th percentile

1.07 (0.83, 1.37)

1.14 (0.88, 1.48)

1.04 (0.80, 1.36)

> 75^th percentile

0.92 (0.71, 1.18)

1.03 (0.79, 1.35)

0.92 (0.69, 1.22)

Continuous****

0.95 (0.87, 1.05)

0.99 (0.89, 1.09)

0.94 (0.85, 1.05)