Table 3.
Odds Ratio (OR) and 95% Confidence Interval (CI) of spontaneous preterm birth sub-types according to maternal sleep duration and vital exhaustion during the first six months of pregnancy, Lima, Peru, 2009-2010
| Term controls (N = 480) | Spontaneous Preterm Labor (SPTL) (N = 245) | Preterm Premature Rupture of Membrane (PPROM) (N = 234) | |||
|---|---|---|---|---|---|
| Exposure parameters | n | n | OR* (95% CI) | n | OR* (95% CI) |
| Hours of sleep per night | |||||
| ≤ 6 hours | 79 | 51 | 1.51 (1.00-2.29) | 56 | 1.60 (1.06-2.40) |
| 7-8 hours | 325 | 143 | 1.00 (referent) | 141 | 1.00 (referent) |
| ≥ 9 hours | 76 | 51 | 1.50 (0.99-2.27) | 37 | 1.17 (0.74-1.83) |
| Complaint of vital exhaustion | |||||
| Never | 185 | 55 | 1.00 (referent) | 44 | 1.00 (referent) |
| Ever | 295 | 190 | 2.21 (1.54-3.15) | 190 | 2.66 (1.81-3.89 |
| 1-3 times/Month | 204 | 106 | 1.81 (1.23-2.67) | 95 | 2.00 (1.32-3.02) |
| 4 times/Month - Weekly | 73 | 73 | 3.34 (2.13-5.24) | 83 | 4.47 (2.81-7.10) |
| Daily | 18 | 11 | 2.17 (0.95-4.93) | 12 | 2.73 (1.21-6.16) |
| P-value for trend | <0.001 | <0.001 | |||
*Adjusted for maternal age, pre-pregnancy weight, unplanned pregnancy, and no vitamin use during pregnancy.
Bolded estimates are statistically significant at the α = 0.05 level.