Management of Placental Transfusion to Neonates After Delivery

Abstract

This review summarizes high-quality evidence supporting delayed umbilical cord clamping to promote placental transfusion to preterm and term neonates. In preterm neonates, delayed cord clamping may decrease mortality and the need for blood transfusions. Although robust data are lacking to guide cord management strategies in many clinical scenarios, emerging literature is reviewed on numerous topics including delivery mode, twin gestations, maternal comorbidities (eg, gestational diabetes, red blood cell alloimmunization, human immunodeficiency virus [HIV] infection, and severe acute respiratory syndrome coronavirus 2 [SARS-CoV-2] infection) and neonatal complications (eg, fetal growth restriction, congenital heart disease, and the depressed neonate). Umbilical cord milking is an alternate method of rapid placental transfusion, but has been associated with severe intraventricular hemorrhage in extremely preterm neonates. Data on long-term outcomes are discussed, as well as potential contraindications to delayed cord clamping. Overall, delayed cord clamping offers potential benefits to the estimated 140 million neonates born globally every year, emphasizing the importance of this simple and no-cost strategy.

Effects of spontaneous first breath on placental transfusion in term neonates born by cesarean section: A randomized controlled trial

“…It is still up for discussion whether placental-to-neonatal transfusion produces net increases in neonatal blood volumes with DCC during a cesarean birth. The lack of uterine contractions before birth may affect the efficiency of placental-to-neonatal transfusion in elective CS ( 38 ). Due to strong uterine tone, optimal placental transfusion is possible in vaginal births, making it possible to wait for least 3 min after delivery before cutting the cord ( 9 , 10 ).…”

Umbilical cord milking-benefits and risks

“…The higher systemic pressure combined with high pulmonary vascular resistance in non-breathing infants may prevent a rise in pulmonary blood flow during milking. Without a pulmonary pop-off, the rise in aortic pressure may result in fluctuations in cerebral blood flow ( 8 ). Understanding how UCM influences hemodynamic parameters is essential.…”

“…However, the trial enrolled substantial numbers ( N = 182) of infants 23–27 weeks' gestation and demonstrated an increase in severe IVH at each of the 10 centers that participated. Whether prior animal data is translatable in these infants is unclear, however there is biological plausibility that the additional blood volume provided by UCM may not be as well tolerated in the extremely preterm infant who lack cerebral autoregulation and have a very fragile germinal matrix which may lead to hemorrhage ( 8 ). Unfortunately, most of the literature on preterm infants comes from small studies or mostly mature infants ( 34 , 90 , 94 , 95 ).…”

“…Early observational studies demonstrated that the infant to placenta blood volume ratio increased from 67%/33% at birth to 87%/13% at the end of placental transfusion ( 7 ). The amount of placental transfusion that occurs may be influenced by various factors, such as uterine contractions, delivery method, length of time from birth to cord clamp, and possibly gravity and the newborn's spontaneous respirations ( 8 ). Placental transfusion is an essential part of the neonatal transition as the increased blood volume affects all organ systems.…”

In Reply:

“…We thank Dr. Lerner for his thoughtful comments regarding our article in the January 2022 issue on the management of placental transfusion. 1 We agree that every planned intervention requires an evidence-based risk–benefit analysis. In several trials, delayed cord clamping has been demonstrated to be safe in late preterm and term neonates.…”