a review of the literature on umbilical cord clamping
Nurse-Midwifery Program, University of Rhode Island College of Nursing, Kingston 02881-2021, USA.
Immediate clamping of the umbilical cord can reduce the red blood
cells an infant receives at birth by more than 50%, resulting in potential
short-term and long-term neonatal problems. Cord clamping studies from
1980 to 2001 were reviewed. Five hundred thirty-one term infants in the
nine identified randomized and nonrandomized studies experienced late
clamping, ranging from 3 minutes to cessation of pulsations, without
symptoms of polycythemia or significant hyperbilirubinemia. Higher red
blood cell flow to vital organs in the first week was noted, and term
infants had less anemia at 2 months and increased duration of early
breastfeeding. In seven randomized trials of preterm infants, benefits
associated with delayed clamping in these infants included higher
hematocrit and hemoglobin levels, blood pressure, and blood volume, with
better cardiopulmonary adaptation and fewer days of oxygen and ventilation
and fewer transfusions needed. For both term and preterm infants, few, if
any, risks were associated with delayed cord clamping. Longitudinal
studies of infants with immediate and delayed cord clamping are needed.