Table 1.
Patient characteristics
| Characteristics | History of termination of pregnancies (%) | Reference group (%) |
|---|---|---|
| Study population | 16000 | 1341894 |
| Maternal age* | ||
| Mean (SD) | 30.41 (5.8) | 30.40 (48) |
| <20 | 525 (3.3) | 22786 (17) |
| 20–25 | 2983 (18.6) | 187355 (14) |
| 26–30 | 4085 (25.5) | 447307 (33.3) |
| 31–35 | 5186 (32.4) | 495546 (36.9) |
| >35 | 3219 (20.1) | 188591 (14.1) |
| Parity* | ||
| 0 | 9265 (57.9) | 613755 (45.7) |
| 1 | 4692 (29.3) | 485287 (36.2) |
| 2 | 1453 (9.1) | 169802 (12.7) |
| 3 | 417 (2.6) | 46910 (3.5) |
| ≥4 | 172 (1.1) | 25822 (1.9) |
| SES* | ||
| High | 3469 (21.7) | 314667 (23.4) |
| Normal | 5488 (34.3) | 608113 (45.3) |
| Low | 6861 (43) | 402254 (30) |
| Ethnicity* | ||
| Dutch | 10304 (64.4) | 1093438 (81.5) |
| Mediterranean | 1184 (7.4) | 105368 (7.9) |
| Other European | 1012 (6.3) | 33728 (2.5) |
| Creole | 1441 (9) | 30226 (2.3) |
| Hindu | 341 (2.1) | 14523 (1.1) |
| Asian | 605 (3.8) | 24408 (1.8) |
| Other | 1086 (6.8) | 31519 (2.3) |
| Smoking* | 180 (1.1) | 5712 (0.4) |
| Drug dependence* | 91 (0.6) | 1232 (0.09) |
| Reproductive history | ||
| Preterm delivery* | 165 (1) | 16122 (1.2) |
| Cervical incompetence/Shirodkar procedure | 3 (0.02) | 381 (0.03) |
| Placenta praevia* | 8 (0.05) | 183 (0.01) |
| Placental abruption | 17 (0.1) | 2023 (0.2) |
| Manual removal of the placenta | 75 (0.5) | 7353 (0.5) |
| Postpartum haemorrhage* | 156 (1) | 19062 (1.4) |
| Caesarean section* | 839 (5.2) | 101884 (7.6) |
| Cervical surgery* | 28 (0.2) | 1424 (0.1) |
| Uterine myoma* | 79 (0.5) | 4732 (0.4) |
| Myomectomy subserous | 5 (0.03) | 257 (0.02) |
| Myomectomy submucous/intramural | 4 (0.03) | 409 (0.03) |
| Index gravidity | ||
| Pyelitis* | 20 (0.1) | 736 (0.05) |
| Polyhydramnios | 5 (0.03) | 234 (0.02) |
| Mode of delivery* | ||
| Spontaneous vaginal delivery | 12048 (75.4) | 1024044 (76.4) |
| Instrumental vaginal delivery | 1682 (10.5) | 143654 (10.7) |
| Elective caesarean delivery | 738 (4.6) | 70345 (5.2) |
| Emergency caesarean delivery | 1520 (9.5) | 102090 (7.6) |
| Perinatal mortality* | 109 (0.7) | 7602 (0.6) |
*p<0.05.
SES, socioeconomic status.