The American College of Obstetricians and Gynecologists recommends that umbilical cord clamping be delayed for at least 30-60 seconds after birth in vigorous preterm and term infants.
Since early studies suggested that up to 90% of the blood transfer from the placenta to the newborn after birth happens with an infant’s first few breaths, it has become common practice to clamp the cord within 15-20 seconds after birth.
In 2012, the ACOG Committee on Obstetric Practice recommended use of delayed umbilical cord clamping in preterm infants, but found a lack of evidence in term infants. “However, more recent randomized controlled trials of term and preterm infants as well as physiologic studies of blood volume, oxygenation, and arterial pressure have evaluated the effects of immediate versus delayed umbilical cord clamping (usually defined as cord clamping at least 30-60 seconds after birth),” wrote the members of the College’s Committee on Obstetric Practice in an updated opinion released on Dec. 21.
These studies showed that around 80 mL of blood is transferred from the placenta within 1 minute of birth, which appears to be facilitated by the newborn’s initial breaths. This initial transfer of blood supplies significant quantities of iron – 40-50 mg/kg of body weight - and is associated with a lower risk of iron deficiency during the first year of life (Obstet Gynecol. 2017;129:e5-10).
The committee cited a 2012 systematic review of the data on preterm infants that found a 39% reduction in the number of infants requiring transfusion for anemia when delayed umbilical cord clamping – defined as a delay of 30-180 seconds – was used, compared with immediate clamping. The review also noted a 41% reduction in the incidence of intraventricular hemorrhage and 38% reduction in necrotizing enterocolitis, compared with immediate umbilical cord clamping.
Similarly in term infants, those who had their umbilical cord clamped early showed significantly lower hemoglobin concentrations at birth and were more likely to have iron deficiency at 3-6 months of age, compared with term infants who had delayed clamping.
The committee did note that preterm infants who experienced delayed cord clamping showed higher peak bilirubin levels, compared with early clamping. In term infants, delayed cord clamping was associated with a small increase in the incidence of jaundice requiring phototherapy, although there were no significant differences in the rates of polycythemia or jaundice overall.
“Consequently, obstetrician-gynecologists and other obstetric care providers adopting delayed cord clamping in term infants should ensure that mechanisms are in place to monitor for and treat neonatal jaundice,” the committee members wrote.
With regards to maternal outcomes, there had been concerns that delayed umbilical cord clamping could increase the risk of maternal hemorrhage. But a review of five trials including more than 2,200 women found no sign of an increase in adverse events such as postpartum hemorrhage, increased blood loss at delivery, blood transfusions, or reduced postpartum hemoglobin levels.
“However, when there is increased risk of hemorrhage (e.g., placenta previa or placental abruption), the benefits of delayed umbilical cord clamping need to be balanced with the need for timely hemodynamic stabilization of the woman,” the authors wrote.
The committee found that skin-to-skin care could still take place with delayed umbilical cord clamping, as gravity was not necessary to facilitate the flow of blood from the placenta to the newborn. They also advised that early care of the newborn could still be carried out, including drying and stimulating for the first breath.
Delayed umbilical cord clamping should also not interfere with active management of the third stage of labor, including the use of uterotonic agents after delivery.
The authors reported having no conflicts of interest.