BACKGROUND AND PURPOSE: 

• Breech presentation occurs in 30 to 35% of pregnancies between 22-28 weeks 
• Best mode of delivery for preterm and extremely preterm breech is unclear  
• Gravovac et al. (BJOG 2018) assessed the safest mode of delivery for preterm breech singletons  

METHODS: 

• Systematic review and meta-analysis  
• Database search of studies comparing outcomes by delivery mode in actively resuscitated breech infants 
  • All published RCTs and observational (cohort and case-control) studies  
• Extremely preterm: Defined as <28 weeks 
• Not actively resuscitated removed so as not to bias toward cesarean section  
• Primary outcomes (stratified by gestational age) 
  • Death (neonatal, before discharge, or by 6 months)  
  • Severe intraventricular hemorrhage (IVH grades III/IV) 

RESULTS: 

• 15 studies were included, totaling 12,335 infants 
• Recommendations based on GRADE methods
  • ‘Strong’ recommendation for those findings that were significant  
• Cesarean delivery associated with decreased odds of death  
  • 23w0d–27w6d: Odds Ratio (OR) 0.59; 95% CI, 0.36-0.95 (strong recommendation for cesarean) 
  • 23w0d-24w6d: OR 0.58; 95% CI, 0.44–0.75 (strong recommendation for cesarean)  
  • 25w0d-26w6d: OR 0.72; 95% CI, 0.34-1.52 (weak recommendation for cesarean) 
  • 27w0d-27w6d: OR 2.04; 95% CI, 0.20-20.62 (weak recommendation against cesarean) 
• Cesarean delivery associated with decreased odds of severe IVH 
  • 23w0d-27w6d: OR 0.51; 95% CI, 0.29-0.91 (strong recommendation for cesarean) 
  • 25w0d-26w6d: OR 0.29; 95% CI, 0.07–1.12 (weak recommendation for cesarean) 
  • 27w0d-27w6d: OR 0.91; 95% CI, 0.27-3.05 (weak recommendation for cesarean) 
• Mean proportion of head entrapment 
  • 1.1% with caesarean delivery vs 5.5% with vaginal delivery in 4 studies 
  • Dührssen incisions were performed in one study for three cases of head entrapment 

CONCLUSION: 

• C-sections were associated with a 41% reduction in odds for death (particularly in the youngest GA bracket) and a 49% reduction in odds for intraventricular hemorrhage in actively resuscitated breech singletons <28 weeks of gestation 
• The authors state that “In infants born between 23+0 and 24+6 weeks, caesarean section was associated with a significant reduction in odds of death before discharge to 6 months corrected age, which according to GRADE would have a strong recommendation.” 
• Limitations include 
  • Data is mostly observational  
  • Scarce data on associated morbidities 

Learn More – Primary Sources:  

What is the safest mode of birth for extremely preterm breech singleton infants who are actively resuscitated? A systematic review and meta-analyses.

Related ObG Topics:

Updated Outcomes Data for Neonates less than 500 Grams at Birth