Table 1.
Maternal clinical characteristics and outcomes in 99253 pregnant women.
| Total | N = 99253 | Percentile |
|---|---|---|
| Singleton | 95967 | 96.69% |
| Twin | 3286 | 3.31% |
| Age (y) | 30.7 ± 4.5 | |
| <25 | 6373 | 6.4% |
| 25–34 | 72356 | 72.9% |
| ≥35 | 20524 | 20.7% |
| Parity | ||
| Nulli | 58336 | 58.8% |
| Pluri (parity 1–3 times) | 40535 | 40.7% |
| Pluri (parity ≥ 4 times) | 382 | 0.4% |
| Gestational age (weeks) | 38.8 ± 2.0 | |
| ≥37 | 88563 | 89.2% |
| 34-36w+6d | 7172 | 7.2% |
| 32-33w+6d | 1672 | 1.7% |
| <32 | 1846 | 1.9% |
| Methods of conception | ||
| Nature | 95893 | 96.6% |
| ART | 3360 | 3.4% |
| Height (cm) | 161.3 ± 4.7 | |
| <160 | 33195 | 62.0% |
| 160–169.9 | 61535 | 33.4% |
| ≥170 | 4523 | 4.6% |
| Pre-pregnancy BMI (kg/m2) | 20.9 ± 3.1 | |
| <18.5 | 22687 | 23.5% |
| 18.5–23.9 | 61085 | 63.3% |
| 24.0–27.9 | 10427 | 10.8% |
| ≥28.0 | 2362 | 2.4% |
| Mode of delivery | ||
| Vaginal delivery | 53798 | 54.2% |
| Cesarean section | 45455 | 45.8% |
| Cesarean section history | 18433 | 18.6% |
| Hypertensive disorders of pregnancy | 5095 | 5.1% |
| Gestation hypertension | 1853 | 1.9% |
| Chronic hypertension | 150 | 0.2% |
| Preeclampsia | 2803 | 2.9% |
| Preeclampsia superimposed | ||
| On chronic hypertension | 289 | 0.3% |
| Postpartum hemorrhage | ||
| ≥1,000 ml (overall population) | 804 | 0.8% |
| Singletons pregnancies subgroup | 717 | 0.75% |
| Twin pregnancies subgroup | 87 | 2.65% |
| Cesarean delivery subgroup | 637 | 1.40% |
| Vaginal delivery subgroup | 167 | 0.31% |