Table 3.
Relative risksa of PPD (EPDS ≥ 13) onset subtypes at 6 months postpartum for 5-μg/m3 change in PM2.5 exposure during pregnancy (N = 509).
| 6-month PPD subtype | No. of cases | RR (95% CI) | P |
|---|---|---|---|
| Late postpartum onset (no PPD at 1 month + PPD at 6 months) | 45 | 2.58 (1.40, 4.73) | 0.002 |
| Chronic postpartum (PPD at 1 and 6 months) | 45 | 1.06 (0.63, 1.76) | 0.83 |
Estimated from modified Poisson regression models with robust error variance, adjusted for maternal age at enrollment, tobacco exposure during pregnancy, maternal education, birth season, gestational age, and NLE score during pregnancy.