Duration of Cord Clamping and Neonatal Outcomes in Very Preterm Infants

Delayed cord clamping (DCC, ≥30 s) increases blood volume in newborns and is associated with fewer blood transfusions and short-term neonatal complications. The optimal timing of cord clamping for very preterm infants should maximize placental transfusion without interfering with stabilization and resuscitation.

We compared the effect of different durations of DCC, 30-45 s vs. 60-75 s, on delivery room (DR) and neonatal outcomes in preterm infants <32 weeks gestational age (GA).

This is a single-center prospective observational study. Data were collected prospectively from eligible infants from two groups: 30-45 s DCC group (January 2008 to February 2011, n = 187) and 60-75 s DCC group (March 2011 to April 2014, n = 166).

The 60-75 s DCC group compared to the 30-45 s DCC group had higher hematocrits at <2 hours (49.2% vs. 47.4%, p = 0.02). In infants <28 weeks GA, the 12-36 hours hematocrit was higher in the 60-75 s DCC group compared to the 30-45 s DCC group (47.9% vs. 42.1%, p = 0.002). The 60-75 s DCC group had reductions in DR intubation (11% vs. 22%, p = 0.004), hypothermia on admission (1% vs. 5%, p = 0.01), surfactant therapy (13% vs. 28%, p = 0.001), intubation in the first 24 hours (20% vs. 34%, p = 0.004), any intubation (27% vs. 40%, p = 0.007), and any red blood cell transfusion (20% vs. 33%, p = 0.008) during the hospitalization compared to the 30-45 s DCC group. These reductions remained significant after adjusting for GA, gender and >48 hours of antenatal steroid exposure. There was no difference between the two groups in neonatal death, intraventricular hemorrhage, chronic lung disease, late onset sepsis, necrotizing enterocolitis and severe retinopathy of prematurity.

In this study cohort increasing DCC duration from 30-45 s to 60-75 s is associated with decreased hypothermia on admission, neonatal respiratory interventions and red blood cell transfusions without increase in neonatal mortality and morbidities.