Table 5.
Relative risks for maternal and perinatal outcomes by completed week of gestation vs. deliveries in the previous week
| Outcomes | Among those that reached 39 0/7 weeks undelivered | Among those that reached 40 0/7 weeks undelivered | ||
|---|---|---|---|---|
| N=2,501 | N=1,537 | |||
|
| ||||
| 40 0/7 to 42 2/7 weeks | 41 0/7 to 42 2/7 weeks | |||
| vs. 39 0/7 to 39 6/7 weeks | vs. 40 0/7 to 40 6/7 weeks | |||
| RR (95%CI) | aRR (95%CI) | RR (95%CI) | aRR (95%CI) | |
|
| ||||
| Maternal outcomes * | ||||
|
| ||||
| Cesarean delivery | 1.52 (1.29, 1.78) | 1.45 (1.24–1.71) | 1.71 (1.45, 2.01) | 1.56 (1.33–1.84) |
|
| ||||
| Hypertensive disorders of pregnancy | 0.71 (0.59, 0.87) | 0.68 (0.56–0.83) | 0.89 (0.65, 1.22) | 0.87 (0.63–1.19) |
|
| ||||
| Peripartum infection | 1.10 (0.92, 1.33) | 1.13 (0.94–1.37) | 0.97 (0.76, 1.25) | 0.99 (0.77–1.27) |
|
| ||||
| Maternal Composite | 0.77 (0.46, 1.29) | 0.85 (0.50–1.44) | 2.02 (1.01, 4.07) | 2.05 (1.00–4.20) |
|
| ||||
| Perinatal-neonatal outcomes † | ||||
|
| ||||
| Perinatal composite | 1.28 (0.92, 1.78) | 1.25 (0.90–1.74) | 1.40 (0.94, 2.08) | 1.42 (0.96–2.12) |
|
| ||||
| NICU admission | 1.17 (0.95, 1.44) | 1.13 (0.92–1.39) | 1.19 (0.92, 1.54) | 1.17 (0.90–1.52) |
aRR, adjusted relative risk; CI, confidence intervals; NICU, neonatal intensive care unit.
Bold indicates p<0.05 for unadjusted comparisons, p<0.0125 for adjusted co-primary outcome comparisons (cesarean and perinatal composite), and significance for adjusted comparisons of secondary outcomes after controlling for multiple comparisons with the false discovery rate method.
*
Models adjusted for maternal age, smoking, and BMI at first clinic visit.
†
Models adjusted for maternal age, smoking, BMI at first clinic visit, and fetal sex.