Indications for caesarean sections at ≥34 weeks among nulliparous women and differential composite maternal and neonatal morbidity

BJOG. 2014 Oct;121(11):1395-402. doi: 10.1111/1471-0528.12669. Epub 2014 Feb 10.


Objective: To compare composite maternal and neonatal morbidities (CMM, CNM) among nulliparous women with primary indications for caesarean section (CS) as acute clinical emergency (group I; ACE), non-reassuring fetal heart rate (group II) and arrest disorder (group III).

Design: A multicentre prospective study.

Setting: Nineteen academic centres in the USA, with deliveries in 1999-2002.

Population: Nulliparous women (n = 9829) that had CS.

Methods: Nulliparous women undergoing CS for three categories of indications were compared using logistic regression model, adjusted for five variables.

Main outcome measures: CMM was defined as the presence of any of the following: intrapartum or postpartum transfusion, uterine rupture, hysterectomy, cystotomy, ureteral or bowel injury or death; CNM was defined as the presence of any of the following: umbilical arterial pH <7.00, neonatal seizure, cardiac, hepatic, renal dysfunction, hypoxic ischaemic encephalopathy or neonatal death.

Results: The primary reasons for CS were ACE in 1% (group I, n = 114) non-reassuring FHR in 29% (group II; n = 2822) and failed induction/dystocia in the remaining 70% (group III; n = 6893). The overall risks of CMM and CNM were 2.5% (95% confidence intervals, CI, 2.2-2.8%) and 1.9% (95% CI 1.7-2.2), respectively. The risk of CMM was higher in group I than in group II (RR 4.1, 95% CI 3.1, 5.3), and group III (RR 3.2, 95% CI 2.7, 3.7). The risk of CNM was also higher in group I than in group II (RR 2.8, 95% CI 2.3, 3.4) and group III (RR 14.1, 95% CI 10.7, 18.7).

Conclusions: Nulliparous women who have acute clinically emergent caesarean sections are at the highest risks of both composite maternal and neonatal morbidity and mortality.

Keywords: Caesarean; composite maternal or neonatal morbidity; nulliparous.

Publication types

  • Multicenter Study

MeSH terms

  • Adult
  • Cesarean Section* / mortality
  • Cesarean Section* / statistics & numerical data
  • Cystotomy / adverse effects
  • Cystotomy / mortality
  • Emergency Medicine*
  • Female
  • Heart Diseases / epidemiology
  • Humans
  • Hypoxia-Ischemia, Brain / epidemiology
  • Hysterectomy / adverse effects
  • Hysterectomy / mortality
  • Infant, Newborn
  • Intestinal Diseases / epidemiology
  • Kidney Diseases / epidemiology
  • Liver Diseases / epidemiology
  • Male
  • Morbidity
  • Parity*
  • Pregnancy
  • Prospective Studies
  • Risk Factors
  • Seizures / epidemiology
  • Umbilical Arteries / pathology
  • United States / epidemiology
  • Uterine Diseases / mortality