Table 3.
Period of pregnancy (weeks) |
Severely PTBs (n = 1,188) OR [95 % CI] |
Moderately PTBs (n = 1,701) OR [95 % CI] |
Mildly PTBs (n = 14,397) OR [95 % CI] |
SGA (n = 16,520) OR [95 % CI] |
---|---|---|---|---|
1–4 | 1.89 [1.33, 2.68] | 1.91 [1.44, 2.54] | 1.16 [1.05, 1.28] | 1.04 [0.94, 1.14] |
5–8 | 0.90 [0.60, 1.33] | 1.09 [0.78, 1.52] | 1.08 [0.96, 1.21] | 0.98 [0.88, 1.10] |
9–12 | 1.27 [0.87, 1.87] | 1.64 [1.18, 2.28] | 1.26 [1.12, 1.1] | 1.09 [0.98, 1.22] |
13–16 | 0.71 [0.49, 1.03] | 0.96 [0.71, 1.32] | 0.96 [0.86, 1.07] | 1.05 [0.95, 1.17] |
17–20 | 1.69 [1.15, 2.50] | 0.92 [0.67, 1.27] | 1.16 [1.03, 1.30] | 0.87 [0.78, 0.98] |
21–24 | – | 0.88 [0.64, 1.21] | 0.83 [0.74, 0.93] | 1.11 [0.98, 1.23] |
25–28 | – | 1.93 [1.43, 2.60] | 1.10 [0.99, 1.23] | 1.01 [0.92, 1.12] |
29–32 | – | – | 1.30 [1.17, 1.46] | 1.01 [0.91, 1.12] |
33–36 | – | – | – | 0.94 [0.84, 1.04] |
OR odds ratio, CI confidence intervals, SGA small for gestational age, WIC Women, Infants, and Children, BMI body mass index
Adjusted for pollutant concentrations during the other 4-week periods, season, race, level of education, age, BMI status, support received from infant’s father, receipt of WIC services; trimester prenatal care initiated; parity; and type of payment for delivery