Table 1.
Cohort characteristics according to indication for preterm birth.
| Preeclampsia/HELLP | All other indications | p-value | |||
|---|---|---|---|---|---|
| n = 2,652 | n = 13,383 | ||||
| Gestational age at birth, mean weeks (SD) | 29.0 (2.3) | 28.1 (2.5) | <0.001 | ||
| Birth weight, mean grams (SD) |
1,001 (312) | 1,028 (301) | 0.001 | ||
| Female gender, n (%) | 1,427 (53.8) | 51.9–55.7 | 6,319 (47.2) | 46.4–48.1 | <0.001 |
| Multiple gestation, n (%) | 365 (13.8) | 12.5–15.1 | 5,261 (39.3) | 38.5–40.1 | <0.001 |
| Antenatal steroids, n (%) | 2,457 (92.9) | 91.9–93.8 | 12,191 (91.2) | 90.7–91.7 | 0.005 |
| Mode of delivery | |||||
| Vaginal delivery, n (%) | 20 (0.8) | 0.5–1.1 | 1,431 (10.7) | 10.2–11.3 | |
| Elective cesarean section, n (%) | 2,454 (92.9) | 91.9–93.8 | 10,396 (77.9) | 77.2–78.6 | <0.001* |
| Emergency cesarean section, n (%) | 168 (6.4) | 5.5–7.3 | 1,525 (11.4) | 10.9–12.0 | |
Data are given as mean (SD) or n (%) with 95% confidence interval. Percentages are given as column percentages; *for all modes of delivery.