Rates and unadjusted odds ratios of preterm birth and low birth weight for interpregnancy intervals
| Preterm birth | Low birth weight | |||
|---|---|---|---|---|
| Interval in months | Prevalence | Odds ratio (95% CI) | Prevalence | Odds ratio(CI) |
| *Not significant. | ||||
| ≤4.00 | 8.3% | 3.04(1.61 to 5.73) | 11.8% | 3.71(2.14 to 6.42) |
| 4.01–8.00 | 5.1% | 1.78(1.08 to 2.92) | 7.7% | 2.32(1.53 to 3.52) |
| 8.01–12.00 | 3.3% | 1.15(0.72 to 1.83)* | 4.0% | 1.16(0.76 to 1.78)* |
| 12.01–24.00 | 2.6% | 0.91(0.66 to 1.25)* | 3.4% | 0.97(0.73 to 1.30)* |
| 24.01–36.00 | 2.9% | 1.00 | 3.5% | 1.00 |
| ≥36.01 | 4.2% | 1.45(1.09 to 1.93) | 3.9% | 1.13(0.86 to 1.48)* |