Gestational age at delivery in women with and without a history of pregnancy termination
| Gestational age (weeks) | History of termination of pregnancies (%) | Reference group (%) | cOR (95%CI) | aOR (95%CI) |
|---|---|---|---|---|
| 20+0–23+6 | 43 (0.3) | 1966 (0.1) | 1.83 (1.35 to 2.48) | 1.61 (1.13 to 2.30) |
| 24+0–28+6 | 56 (0.4) | 2658 (0.2) | 1.76 (1.35 to 2.30) | 1.67 (1.22 to 2.28) |
| 29+0–32+6 | 80 (0.5) | 5393 (0.4) | 1.24 (0.99 to 1.55) | 1.36 (1.07 to 1.74) |
| 33+0–36+6 | 602 (3.8) | 47002 (3.5) | 1.07 (0.99 to 1.16) | 1.04 (0.95 to 1.14) |
| ≥37 | 15152 (95.1) | 1268013 (95.7) | Reference group | Reference group |
aORs are adjusted for maternal age, ethnicity, SES, parity, smoking, drug dependence, pyelitis, polyhydramnios, history of SPTB, history of cervical incompetence or Shirodkar procedure, history of uterine myoma and history of cervical surgery.
aOR, adjusted OR; cOR, crude OR; SES, socioeconomic status; SPTB, spontaneous preterm birth.