BACKGROUND AND PURPOSE:

• ACOG guidelines now call for waiting at least 30 to 60 seconds after birth before clamping the cord in preterm infants (see ‘Related ObG Topics’ below) if resuscitation unnecessary
• Guidelines based on multiple studies showing benefit such as prevention of necrotizing enterocolitis and infection
• Other guideline committees concur, however this practice is still not universal
• Data limited with respect to mortality or incidence of neurodevelopmental disability
• Mordi et al. (NEJM, 2017) determined the optimal timing for umbilical-cord clamping following delivery in preterm infants

METHODS:

• Randomized controlled trial (RCT)
• Australian Placental Transfusion Study (APTS)
• Women expecting to delivery before 30 weeks gestation were randomized into
  • Immediate clamping of umblicial cord (≤10 seconds after delivery)
  • Delayed clamping (≥60 seconds after delivery)
• The primary outcome was composite of death or major morbidity (defined as severe brain injury on postnatal ultrasonography, severe retinopathy of prematurity, necrotizing enterocolitis, or late-onset sepsis) by 36 weeks of postmenstrual age
• Analyses were performed on an intention-to-treat basis

RESULTS:

• 1566 liveborn < 30 weeks of gestation
  • 782 were assigned to immediate cord clamping (median time 5 seconds)
  • 784 were assigned to delayed cord clamping (median time 60 seconds)
• There was no significant difference in composite of death or major morbidity between groups (37% delayed vs 37.2% immediate; P=0.96)
• Mortality rate alone
  • Mortality was initially lower in the delayed group (6.4% vs 9.0%)
  • Adjusting for confounders, there was no significant difference
• There were no significant differences between the two groups in the incidences of chronic lung disease or other major morbidities

CONCLUSION:

• Delayed cord clamping did not result in lower incidence of combined outcome of death or major morbidity in preterm infants at 36 weeks of gestation, compared to immediate clamping
• The findings in this study differ from previous studies that did show less morbidity in the delayed clamping groups
  • Authors suggest that infants in the current study may have been less ill
  • A properly powered trial to assess mortality would require > 11,000 patients

Learn More – Primary Sources:

Delayed versus Immediate Cord Clamping in Preterm Infants

Related ObG Topics: