Categories for high-risk factors*
| Category | High-risk factors |
| Physical findings | Age ≥40 years, body weight >80 kg before pregnancy, primiparas with body mass index >25 in the antepartum period. |
| Medical treatment for complication | Thyroid disease, connective tissue disorder, kidney disease, mental disorder, epilepsy, bronchial asthma, neurological disorder, blood-type incompatible pregnancy, haematological disease, heart disease, uterine cancer, Rhesus (D) alloimmunization in pregnancy, high blood pressure, hypertensive disorders of pregnancy, HIV positive, diabetes, gestational diabetes mellitus, antiphospholipid syndrome, pelvic fracture, placenta previa, pregnancy following conisation, premature birth, non-cephalic presentation after 36 weeks’ gestation, multiple pregnancy, intrauterine growth retardation, pregnancy following myomectomy, high-grade cervical dysplasia, abdominal surgery other than caesarean section performed or planned during the pregnancy. |
| Pregnancy course | IVF, pregnancy after extensive fertility treatment, undergoing treatment for sexually transmitted disease, risk of mother-to-child transmission, two or fewer pregnancy check-ups, oligohydramnios, polyhydramnios, placenta previa because of previous caesarean section, received definitive diagnosis of fetal malformation or chromosomal abnormalities. |
| History of gynaecological diseases | Large uterine fibroids, postuterine surgery, caesarean section in previous delivery, placental abruption, underwent or plans to undergo abdominal surgery other than caesarean section, cervical incompetency, two or more spontaneous abortions, congenital disease, history of blood-type incompatible pregnancy, eclampsia/HELLP syndrome, gestational diabetes mellitus, stillbirth, neonatal death, delivery of infant <2500 g, severe gestational hypertension ≥160/110 mm Hg, history of delivering infant with major malformations. |
*We defined low-risk labour as labour without any of these high-risk factors.
HELLP, Hemolytic anemia, Elevated liver enzymes, Low Platelet count.