Table 4.
Regression analyses evaluating sleep quality and perceived stress at 32 weeks gestation and whether quality of sleep mediates the relationship between perceived stress at 32 weeks' gestation and preterm birth
| β estimate | Odds Ratio | 95% CI | R2 Change | |
|---|---|---|---|---|
| Crude Model | 0.10 | 1.10 | 1.03-1.18 | |
| Model 1 | 0.11 | |||
| Obstetric Risk | 0.20 | 1.22 | 0.60-2.50 | |
| Income Category (> $60,000) | −1.66 | 0.19 | 0.01-0.82 | |
| Income Category ($30,000-$60,000) | 0.91 | 2.49 | 0.32-4.38 | |
| PSS (Time 3) | 0.08 | 1.08 | 1.00-1.16 | |
| Model 2 | 0.12 | |||
| Obstetric Risk | 0.26 | 1.30 | 0.63-2.71 | |
| Income Category (> $60,000) | −1.59 | 0.20 | 0.01-0.98 | |
| Income Category ($30,000-$60,000) | 0.91 | 2.49 | 0.33-4.85 | |
| PSQI (Time 3) | 0.09 | 1.10 | 0.89-1.36 | |
| PSS (Time 3) | 0.06 | 1.06 | 0.97-1.15 |
The Crude Model represents a logistic regression in which perceived stress at 32 weeks' gestation predicts preterm birth. Model 1 was adjusted for obstetric risk (none or 1+) and income categories (< $30,000, $30,000–$60,000, and > $60,000). Model 2 was adjusted for income, obstetric risk, and for quality of sleep at 32 weeks' gestation.