Comparison of effect of CTG + STan with CTG alone on emergency Cesarean section rate: STan Australian Randomized controlled Trial (START)

S. Kuah, B. Simpson, A. Salter, G. Matthews, J. Louise, J. Bednarz, E. Chandraharan, I. Symonds, A. McPhee, B. W. Mol, D. Turnbull, C. Wilkinson

Research output: Contribution to journalArticlepeer-review

2 Citations (Scopus)


Objective: To investigate whether use of ST analysis of the fetal electrocardiogram (STan) as an adjunct to continuous cardiotocography (CTG) reduces the rate of emergency Cesarean section (EmCS) compared with CTG alone. Methods: This was a randomized controlled trial of patients with a singleton fetus in cephalic presentation at ≥ 36 weeks' gestation, requiring continuous electronic fetal monitoring during labor at a tertiary maternity hospital in Adelaide, Australia, between January 2018 and July 2021. Participants were randomized to undergo CTG + STan or CTG alone. The calculated sample size was 1818 participants. The primary outcome was EmCS. Secondary outcomes included metabolic acidosis, a composite adverse perinatal outcome, and other maternal and neonatal morbidity and safety outcomes. Results: The present study enrolled 970 women, of whom 967 were included in the primary analysis. EmCS occurred in 107/482 (22.2%) deliveries in the CTG + STan arm and in 107/485 (22.1%) in the CTG arm (adjusted relative risk, 1.02 (95% CI, 0.81–1.27); P = 0.89). There was no difference in the rate of adverse maternal or neonatal outcomes between arms. Conclusions: The addition of STan as an adjunct to continuous CTG did not reduce the EmCS rate. The smaller-than-anticipated sample size meant that this study was underpowered to detect absolute differences of ≤ 5% and, therefore, this negative finding could be due to a Type-2 error.

Original languageEnglish
Pages (from-to)462-470
Number of pages9
JournalUltrasound in Obstetrics and Gynecology
Issue number4
Publication statusPublished or Issued - Oct 2023


  • CTG
  • Cesarean section
  • RCT
  • ST analysis
  • STan
  • cardiotocography
  • fetal ECG
  • fetal electrocardiography
  • intrapartum fetal monitoring
  • randomized controlled trial

ASJC Scopus subject areas

  • Radiological and Ultrasound Technology
  • Reproductive Medicine
  • Radiology Nuclear Medicine and imaging
  • Obstetrics and Gynaecology

Cite this