Table 4.
Odds ratios and 95% CIs for small for gestational age (SGA) and low birthweight (LBW) per interquartile range (IQR) a increase in PM2.5 and black carbon among 56,633 term births, overall and by trimester of pregnancy
| Entire Pregnancy | First Trimester | Second Trimester | Third Trimester | |
|---|---|---|---|---|
| Small for Gestational Age | ||||
| PM2.5 | ||||
| Modeled | 1.09 (0.98, 1.21) | 1.00 (0.95, 1.06) | 1.04 (0.99, 1.1) | 1.02 (0.97, 1.08) |
| Monitored | 1.15 (1.00, 1.31)* | 1.00 (0.95, 1.06) | 1.05 (0.99, 1.11) | 1.01 (0.97, 1.06) |
| Black Carbon | ||||
| Modeled | 1.04 (0.99, 1.08) | 1.03 (0.99, 1.06) | 1.03 (0.99, 1.07) | 1.03 (0.99, 1.07) |
| Monitored | 0.96 (0.83, 1.11) | 0.99 (0.93, 1.05) | 0.97 (0.92, 1.02) | 1.03 (0.98, 1.08) |
| Low Birthweight | ||||
| PM2.5 | ||||
| Modeled | 1.05 (0.84, 1.29) | 0.96 (0.86, 1.08) | 1.03 (0.92, 1.16) | 1.05 (0.96, 1.16) |
| Monitored | 0.92 (0.71, 1.19) | 0.94 (0.84, 1.04) | 1.01 (0.91, 1.13) | 1.03 (0.95, 1.13) |
| Black Carbon | ||||
| Modeled | 1.01 (0.93, 1.10) | 1.01 (0.94, 1.09) | 1.02 (0.95, 1.09) | 1.01 (0.94, 1.09) |
| Monitored | 0.81 (0.60, 1.08) | 1.03 (0.91, 1.17) | 0.88 (0.79, 0.98)* | 1.03 (0.94, 1.13) |
All models adjusted for maternal age, gestational age, tobacco, parity, maternal education, maternal race, maternal insurance, marital status, last menstrual period, and neighborhood socioeconomic status. Models of LBW are additionally adjusted for gestational age.We used multiple imputation to account for covariates with missing data: tobacco (13.7% missing), parity (2.4% missing), maternal education (3.7% missing), maternal race (8.4% missing), maternal insurance (0.6% missing), and marital status (1.0%).
IQR is 2.5 µg/m3 for PM2.5 and 0.11 µg/m3 for black carbon.
p<0.05