Clinical Health Updates

Delayed cord clamping in full-term infants reduces risk of anemia

Clinical Question:
Should we routinely delay umbilical cord clamping in full-term infants for at least 2 minutes?

Bottom Line:
There is no evidence that routinely delaying clamping of the umbilical cord for at least 2 minutes after the birth of full-term infants increases the risk of any significant clinical outcome. Infants with late clamping are at a reduced risk of low ferritin levels and stored iron levels up to 6 months of age. Since there may be some potential long-term risks associated with anemia in the first 6 months of life, strong consideration should be given to routinely delaying the clamping of umbilical cords postdelivery. Additional large randomized trials that include maternal outcomes are needed.

Hutton EK, Hassan ES. Late vs early clamping of the umbilical cord in full-term neonates. Systematic review and meta-analysis of controlled trials. JAMA 2007;297:1241-1252.

Study Design:
Meta-analysis (other)

With few exceptions, the umbilical cord of every newborn is clamped and cut at birth, yet the optimal timing for this intervention remains controversial. The authors compared the potential benefits and harms of late vs early cord clamping in term infants.
Search of 6 electronic databases (on November 15, 2006, starting from the beginning of each):
1. the Cochrane Pregnancy and Childbirth Group trials register
2. the Cochrane Neonatal Group trials register
3. the Cochrane library
hand search of secondary references in relevant studies; and contact of investigators about relevant published research. Controlled trials comparing late vs early cord clamping following birth in infants born at 37 or more weeks’ gestation. Two reviewers independently assessed eligibility and quality of trials and extracted data for outcomes of interest: infant hematologic status; iron status; and risk of adverse events such as jaundice, polycythemia, and respiratory distress. The meta-analysis included 15 controlled trials (1912 newborns). Late cord clamping was delayed for at least 2 minutes (n = 1001 newborns), while early clamping in most trials (n = 911 newborns) was performed immediately after birth. Benefits over ages 2 to 6 months associated with late cord clamping include improved hematologic status measured as hematocrit (weighted mean difference [WMD], 3.70%; 95% confidence interval [CI], 2.00%-5.40%); iron status as measured by ferritin concentration (WMD, 17.89; 95% CI, 16.58-19.21) and stored iron (WMD, 19.90; 95% CI, 7.67-32.13); and a clinically important reduction in the risk of anemia (relative risk (RR), 0.53; 95% CI, 0.40-0.70). Neonates with late clamping were at increased risk of experiencing asymptomatic polycythemia (7 studies [403 neonates]: RR, 3.82; 95% CI, 1.11-13.21; 2 high-quality studies only [281 infants]: RR, 3.91; 95% CI, 1.00-15.36).