Early versus delayed umbilical cord clamping in preterm infants.
BACKGROUND
Optimal timing for clamping of the umbilical cord at birth is unclear. Early clamping allows for immediate resuscitation of the newborn. Delaying clamping may facilitate transfusion of blood between the placenta and the baby.


OBJECTIVE
To delineate the short- and long-term effects for infants born at less than 37 completed weeks' gestation, and their mothers, of early compared to delayed clamping of the umbilical cord at birth.


METHODS
We searched the Cochrane Pregnancy and Childbirth Group trials register (2 February 2004), the Cochrane Neonatal Group trials register (2 February 2004), the Cochrane Central Register of Controlled Trials (The Cochrane Library, Issue 1, 2004), PubMed (1966 to 2 February 2004) and EMBASE (1974 to 2 February 2004).


METHODS
Randomized controlled trials comparing early with delayed (30 seconds or more) clamping of the umbilical cord for infants born before 37 completed weeks' gestation.


METHODS
Three reviewers assessed eligibility and trial quality.


RESULTS
Seven studies (297 infants) were eligible for inclusion. The maximum delay in cord clamping was 120 seconds. Delayed cord clamping was associated with a higher hematocrit four hours after birth (four trials, 134 infants; weighted mean difference 5.31, 95% confidence interval (CI) 3.42 to 7.19), fewer transfusions for anaemia (three trials, 111 infants; relative risk (RR) 2.01, 95% CI 1.24 to 3.27) or low blood pressure (two trials, 58 infants; RR 2.58, 95% CI 1.17 to 5.67) and less intraventricular haemorrhage (five trials, 225 infants; RR 1.74, 95% CI 1.08 to 2.81) than early clamping.


CONCLUSIONS
Delaying cord clamping by 30 to 120 seconds, rather than early clamping, seems to be associated with less need for transfusion and less intraventricular haemorrhage. There are no clear differences in other outcomes.
Rabe
H
H
Trevor Mann Baby Unit, Brighton and Sussex University Hospitals, Royal Sussex Country Hospital, Eastern Road, Brighton, UK, BN2 5BE. heike.rabe@bsuh.nhs.uk
Reynolds
G
G
Diaz-Rossello
J
J
D001803:Blood Transfusion / Q000706:statistics & numerical data; D002543:Cerebral Hemorrhage / Q000517:prevention & control; D003250:Constriction; D006400:Hematocrit; D006801:Humans; D007231:Infant, Newborn; D007234:Infant, Premature / Q000097:blood; D016032:Randomized Controlled Trials as Topic; D012120:Respiration Disorders; D013997:Time Factors; D014470:Umbilical Cord