Yan Chen, Euan Wallace, Peta Forder, Adrienne Kirby, Shabina Ariff, David Osborn, Graham Reynolds, John Simes, Kei Lui, Koert de Waal, Michelle Jeffery, Arvind Sehgal, Kjersti Aagaard, Margo Pritchard, Scott Morris, Roger Soll, Daniele de Luca, Lumaan Sheikh, Nicholas Evans, Leslie Young, Andrew Gill, Walid El-Naggar, Anthony Keech, Alpana Ghadge, Val Gebski, Andrew Watkins, Himanshu Popat, Lisa Askie, David Sweet, Ian Wright, Guan Koh, Katie Groom, Michael Belfort, Lucille Sebastian, Paul Colditz, Mohamed Abdel-Latif, Michael Fogarty, William Tarnow-Mordi, Martin Kluckow, Kristy Robledo, Harshad Patel, Joanna Gullam, David Isaacs, Wendy Hague, Rebecca Brown, Sarah Finlayson, Neil Marlow, Mohan Pammi, Susan Walker, Jonathan Morris, John Newnham, Lelia Duley, Helen Liley, Philip Weston, Karen Simmer
Background The preferred timing of umbilical-cord clamping in preterm infants is unclear. Methods We randomly assigned fetuses from women who were expected to deliver before 30 weeks of gestation to either immediate clamping of the umbilical cord (≤10 seconds after delivery) or delayed clamping (≥60 seconds after delivery). The primary composite outcome was 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, accounting for multiple births. Results Of 1634 fetuses that underwent randomization, 1566 were born alive before 30 weeks of gestation; of these, 782 were assigned to immediate cord clamping and 784 to delayed cord clamping. The median time between delivery and cord clamping was 5 seconds and 60 seconds in the respective groups. Complete data on the primary outcome were available for 1497 infants (95.6%). There was no significant difference in the incidence of the primary outcome between infants assigned to delayed clamping (37.0%) and those assigned to immediate clamping (37.2%) (relative risk, 1.00; 95% confidence interval, 0.88 to 1.13; P=0.96). The mortality was 6.4% in the delayed-clamping group and 9.0% in the immediate-clamping group (P=0.03 in unadjusted analyses; P=0.39 after post hoc adjustment for multiple secondary outcomes). There were no significant differences between the two groups in the incidences of chronic lung disease or other major morbidities. Conclusions Among preterm infants, delayed cord clamping did not result in a lower incidence of the combined outcome of death or major morbidity at 36 weeks of gestation than immediate cord clamping. (Funded by the Australian National Health and Medical Research Council [NHMRC] and the NHMRC Clinical Trials Centre; APTS Australian and New Zealand Clinical Trials Registry number, ACTRN12610000633088 .).