Effect of timing of umbilical cord clamping of term infants on maternal and neonatal outcomes

 

Abstract

Background

Policies for timing of cord clamping vary, with early cord clamping generally carried out in the first 60 seconds after birth, whereas later cord clamping usually involves clamping the umbilical cord greater than one minute after the birth or when cord pulsation has ceased.

Objectives

To determine the effects of different policies of timing of cord clamping at delivery of the placenta on maternal and neonatal outcomes.

Search strategy

We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (December 2007).

Selection criteria

Randomised controlled trials comparing early and late cord clamping.

Data collection and analysis

Two review authors independently assessed trial eligibility and quality and extracted data.

Main results

We included 11 trials of 2989 mothers and their babies. No significant differences between early and late cord clamping were seen for postpartum haemorrhage or severe postpartum haemorrhage in any of the five trials (2236 women) which measured this outcome (relative risk (RR) for postpartum haemorrhage 500 mls or more 1.22, 95% confidence interval (CI) 0.96 to 1.55). For neonatal outcomes, our review showed both benefits and harms for late cord clamping. Following birth, there was a significant increase in infants needing phototherapy for jaundice (RR 0.59, 95% CI 0.38 to 0.92; five trials of 1762 infants) in the late compared with early clamping group. This was accompanied by significant increases in newborn haemoglobin levels in the late cord clamping group compared with early cord clamping (weighted mean difference 2.17 g/dL; 95% CI 0.28 to 4.06; three trials of 671 infants), although this effect did not persist past six months. Infant ferritin levels remained higher in the late clamping group than the early clamping group at six months.

Authors' conclusions

One definition of active management includes directions to administer an uterotonic with birth of the anterior shoulder of the baby and to clamp the umbilical cord within 30-60 seconds of birth of the baby (which is not always feasible in practice). In this review delaying clamping of the cord for at least two to three minutes seems not to increase the risk of postpartum haemorrhage. In addition, late cord clamping can be advantageous for the infant by improving iron status which may be of clinical value particularly in infants where access to good nutrition is poor, although delaying clamping increases the risk of jaundice requiring phototherapy.

 

Plain language summary

Effect of timing of umbilical cord clamping at birth of term infants on mother and baby outcomes

At the time of birth, the infant is still attached to the mother via the umbilical cord, which is part of the placenta. The infant is usually separated from the placenta by clamping the cord. The timing of this clamping is one part of the third stage of labour (the time from birth until delivery of the placenta) which can vary according to clinical policy and practice. Early cord clamping is believed to lead to a reduced risk of bleeding after birth (postpartum haemorrhage). This review of 11 trials showed no significant difference in postpartum haemorrhage rates when early and late cord clamping were compared. For neonatal outcomes it is important to weigh the growing evidence that delayed cord clamping confers improved iron status in infants up to six months after birth, with a possible additional risk of jaundice that requires phototherapy.