Table 4.
Crude and adjusteda HRs (95% CIs) for preterm birth and gestational age specific TTHM exposure averages by payment source for prenatal care.
| 2nd Trimester
|
4 Weeks before birth
|
|||
|---|---|---|---|---|
| TTHM (μg/L) | Governmentb (n = 1,129) | Privatec (n = 1,684) | Governmentb (n = 1,129) | Privatec (n = 1,684) |
| Crude | ||||
| < 40 | 1.00 | 1.00 | 1.00 | 1.00 |
| 40 to < 60 | 0.88 (0.75–1.02) | 0.92 (0.81–1.04) | 1.01 (0.84–1.23) | 0.92 (0.79–1.08) |
| ≥ 60 | 0.84 (0.71–0.99) | 0.88 (0.77–1.01) | 1.19 (0.98–1.44) | 0.94 (0.80–1.10) |
| Adjusted | ||||
| < 40 | 1.00 | 1.00 | 1.00 | 1.00 |
| 40 to < 60 | 0.88 (0.72–1.07) | 0.87 (0.74–1.03) | 1.07 (0.85–1.34) | 0.96 (0.80–1.15) |
| ≥ 60 | 0.83 (0.67–1.04) | 0.82 (0.69–0.99) | 1.39 (1.06–1.81) | 1.00 (0.79–1.25) |
| Per 10 μg/L | 0.96 (0.91–1.02) | 0.95 (0.90–1.00) | 1.03 (0.96–1.11) | 1.00 (0.95–1.06) |
HRs were adjusted for infant sex, marital status, adequacy of prenatal care, maternal age, maternal race and ancestry, maternal education, parity, maternal smoking, conception season, birth season, per-capita income, previous preterm or SGA infant, previous-trimester TTHM exposure, and the presence of one or more maternal disease factors including lung disease, diabetes, eclampsia, hydramnios, chronic hypertension, pregnancy-related hypertension, incompetent cervix, renal disease, uterine bleeding, and inappropriate maternal weight gain/loss.
Source of payment was government or Healthy Start.
Source of payment was private or health maintenance organization.