Table 2.
Patient, pregnancy, and delivery characteristics.
| 1992 | 2000 | 2008 | 2016 | |
|---|---|---|---|---|
| Number of women | 67477 | 60987 | 68195 | 64323 |
| Nulliparous women (%) | 45.9 | 46.2 | 46.9 | 45.1 |
| Mean age (y) | 26.4 | 27.5 | 28.1 | 28.9 |
| Age ≥ 35 y (%) | 2.5 | 5.1 | 7.7 | 10.1 |
| Age < 20 y (%) | 3.8 | 4.3 | 3.7 | 2.3 |
| Multiparous women (%) | 54.1 | 53.8 | 53.1 | 54.9 |
| Mean age (y) | 29.6 | 30.7 | 31.1 | 31.6 |
| Age ≥ 35 y (%) | 9.6 | 15.8 | 20.1 | 22.4 |
| Artificial reproduction technology (ART) | ||||
| Ovulation induction | 1.4 | 1.7 | 2.1 | 2.6 |
| IVF/ICSI (%) | 0.8 | 1.7 | 3.3 | 4.6 |
| Multiple pregnancy (%) | 1.6 | 1.8 | 1.9 | 1.7 |
| Preterm birth <37 w (%) | 5.6 | 7.1 | 7.4 | 7.6 |
| Preterm birth <32 w (%) | 0.8 | 1.0 | 1.0 | 1.2 |
| Epidural (%) | 34.8 | 61.7 | 67.4 | 70.3 |
| Labor induction (%) Po | 27.8 | 30.4 | 25.9 | 25.6 |
| Labor induction (%) Pn | 28.4 | 30.1 | 24.8 | 21.8 |
| Cesarean section (%) | 11.8 | 16.4 | 19.5 | 20.9 |
| Instrumental delivery (%) | 14.5 | 12.4 | 10.4 | 9.8 |
| Number of births | 68613 | 62122 | 69466 | 65440 |
| Birth weight | ||||
| <1500 g | 0.9 | 1.1 | 1.1 | 1.2 |
| 1500-2499 g | 5.2 | 5.7 | 5.8 | 5.7 |
| 2500-3999 g | 85.1 | 85.0 | 84.1 | 84.3 |
| 4000-4499 g | 7.8 | 7.2 | 7.9 | 7.8 |
| ≥4500 g | 1.0 | 0.9 | 1.1 | 1.0 |
| Stillbirth (%) | 0.54 | 0.45 | 0,42 | 0,44 |
| Early neonatal death (%) | 0.30 | 0.23 | 0.20 | 0.18 |
| Infant death (%) | 0.66 | 0.46 | 0.39 | 0.37 |
p < 0.001.