Safety of Delayed Umbilical Cord Clamping in Preterm Neonates Less than 34 weeks Gestation
To the Editor: Delayed cord clamping (DCC) is recommended in infants born at or above 34 wk; however, there is a concern about its safety in babies born at less than 34 wk [1, 2, 3]. We conducted a study with a primary objective of comparing the rates of hyperbilirubinemia and polycythemia during initial 7 d in infants born at less than 34 wk of gestation who were randomized to either DCC by 120 s or early cord clamping (ECC) within less than 30 s.
Hundred pregnant women were randomly subjected to DCC or ECC at the time of birth in a tertiary referral hospital setting. Blood samples of the newborns were taken at 48 h and 7 d for hematocrit measurements. Serum bilirubin levels were estimated once the infants had clinically significant jaundice or at 72 h.
Mean hematocrit at 48 h was 56.0 ± 2.5% in DCC as compared to 45.5 ± 2.0% in ECC and at 72 h, hematocrit was 51.6 ± 2.3% in DCC as compared to 42.1 ± 1.6% in ECC. Mean hematocrit at 48 h and 7 d was significantly higher in the DCC group as compared to the ECC group (p < 0.001), suggesting that DCC helps to increase placental transfusion in preterm infants. None of the babies in either group had polycythemia (hematocrit ≥65%).
Mean total serum bilirubin level at 72 h of birth was 6.6 ± 1.2 mg/dl in DCC group and 8.7 ± 1.6 mg/dl in ECC group. There was no increased risk of hyperbilirubinemia in the DCC group. None of the babies in DCC group and one baby in EEC group had required phototherapy.
In our study, delaying umbilical cord clamping up to 120 s after birth as compared to early cord clamping (within 30 s of birth), in infants born at less 34 wk of gestation does not increase the risk of polycythemia, hyperbilirubenemia and need for phototherapy during initial 7 d of life. DCC is also found to be significantly effective in increasing the hematocrit at 48 h and at 7 d of life as compared to ECC with no significant difference in length of NICU and hospital stay between the two groups.
Compliance with Ethical Standards
Compliance with ethical standards was maintained while conducting the study and ethical clearance was obtained from the institutional ethics committee.
Conflict of Interest
Source of Funding
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