Delayed cord clamping vs cord milking in elective cesarean delivery at term: a randomized controlled trial

Abstract

BackgroundDelayed cord clamping has significant beneficial effects for the neonate and its transition to extrauterine life and is therefore common practice at vaginal births in the Netherlands. In 2015, 16% of neonates were born by caesarean section, in 81% of these cases the umbilical cord was clamped and cut immediately. Neonatal benefits of delayed cord clamping are an increased circulating volume of 25-30ml/kg, leading to a higher preload of both right and left ventricle during transition from umbilical to pulmonary circulation, thus maintaining a stable left ventricle output, and to higher neonatal hemoglobin and hematocrit levels 24 to 48 hours postpartum. At present, little is known about whether the above-mentioned neonatal benefits of delayed cord clamping could apply to neonates delivered by caesarean section. In these cases, possible negative effects on neonatal outcomes (i.e., neonatal hypothermia, lower APGAR scores and hyperbilirubinemia) and maternal outcomes (i.e., increased maternal blood loss and higher postoperative infection rate) should also be taken into consideration. ObjectivesTo determine if clamping the umbilical cord after two minutes is superior when compared to cord milking during elective caesarean sections at term, taking both short and long term neonatal and maternal outcomes into consideration. Additionally, to determine if cord milking could be an appropriate alternative to delayed cord clamping. Study DesignA randomized controlled trial was performed in a large secondary care centre in the Netherlands (Amphia Hospital in Breda) from October 2020 to April 2022. A total of 115 patients who underwent an elective caesarean section between 37+0 and 41+6 weeks of gestation were included. Primary outcomes were neonatal hemoglobin and hematocrit levels at 48 hours postpartum, secondary outcomes were divided into neonatal and maternal outcomes. ResultsAfter randomization 58 participants were treated with cord milking and 57 with delayed cord clamping. There were no significant differences regarding demographic characteristics between both groups. There was no significant difference in primary outcomes, with a mean hemoglobin level 48 hours postpartum of 12.1 mmol/L in the delayed cord clamping group and 12.2 mmol/L in the cord milking group (p=0.80). Regarding our secondary outcomes, there were no significant differences regarding Apgar score, neonatal body temperature, maternal blood loss and post-operative infection rate between our intervention groups. ConclusionsHemoglobin and hematocrit levels at 48 hours postpartum showed no significant differences when comparing delayed cord clamping to cord milking. Delayed cord clamping does not lead to increased maternal blood loss or postoperative infections when compared to a method with a much shorter timeframe between delivery and clamping of the umbilical cord, namely cord milking. Additionally, delayed cord clamping did not lead to lower APGAR score or neonatal temperature compared to cord milking. Our research suggests that delayed cord clamping can be safely performed during elective caesarean sections at term. If per operative circumstances do not allow for delayed cord clamping, cord milking can be an appropriate alternative for the neonate at term.