Effects of Umbilical Cord Milking on Term Infants Delivered by Cesarean Section

Effects of cord clamping timing in at-term elective cesarean section on maternal and neonatal outcomes: a randomized trial

PURPOSE

This study aimed to compare the effects of early cord clamping (ECC), delayed cord clamping (DCC), and umbilical cord milking (MC) on maternal and neonatal outcomes in elective cesarean births.

METHODS

We analyzed 204 women with uncomplicated at-term singleton pregnancies, who underwent cesarean birth under regional anesthesia between March and July 2021. The women were randomized into three groups: DCC (clamped 60 s postpartum), ECC (clamped within 15 s postpartum), or MC (clamped after milking five times) group. The neonatal and maternal outcomes of the groups were evaluated.

RESULTS

The duration of the operation was significantly lower (P < 0.001) in the MC group at 50 min (ECC, 60 min; DCC, 60 min), while intraoperative bleeding was significantly higher (P < 0.001) in the ECC group at 500 mL (DCC, 300 mL; MC, 225 mL). The rates of anemia and polycythemia significantly differed (P = 0.049) between the three groups. DCC and MC did not negatively affect maternal and neonatal outcomes compared with ECC.

CONCLUSION

DCC and MC are superior to ECC in terms of short-term maternal and neonatal outcomes in cases of elective cesarean birth under regional anesthesia.

Maternal implications of placental transfusion

Placental transfusion for 30-60 s after delivery is recommended by numerous professional societies and is now a common practice. Numerous studies document neonatal benefit with minimal maternal risk when routine neonatal stabilization and active management of the third stage of labor are undertaken during the period of delayed cord clamping. Maternal outcomes do not show any increased incidence of postpartum hemorrhage, or need for blood product transfusion in the case of vaginal delivery or cesarean section. Fetomaternal hemorrhage is also likely decreased with delayed cord clamping. In the case of fetal anomalies, cord management should be individualized according to each special circumstance, but is unlikely to lead to increased maternal morbidity. While few studies have investigated maternal outcomes with umbilical cord milking, this practice has not been as widely adopted. With careful monitoring of maternal and fetal well-being, a period of placental transfusion following delivery is advised for benefit of the neonate without significant maternal risk.

Umbilical cord milking-benefits and risks

The most common methods for providing additional placental blood to a newborn are delayed cord clamping (DCC) and umbilical cord milking (UCM). However, DCC carries the potential risk of hypothermia due to extended exposure to the cold environment in the operating room or delivery room, as well as a delay in performing resuscitation. As an alternative, umbilical cord milking (UCM) and delayed cord clamping with resuscitation (DCC-R) have been studied, as they allow for immediate resuscitation after birth. Given the relative ease of performing UCM compared to DCC-R, UCM is being strongly considered as a practical option in non-vigorous term and near-term neonates, as well as preterm neonates requiring immediate respiratory support. However, the safety profile of UCM, particularly in premature newborns, remains a concern. This review will highlight the currently known benefits and risks of umbilical cord milking and explore ongoing studies.

Effects of Placental Transfusion on Late Preterm Infants Admitted to a Mother-Baby Unit

OBJECTIVE

Well-appearing late preterm infants admitted to a mother baby unit may benefit from either delayed cord clamping (DCC) or umbilical cord milking (UCM). However, there are concerns of adverse effects of increased blood volume such as polycythemia and hyperbilirubinemia. The purpose of this study is to examine the short-term effects of placental transfusion on late preterm infants born between 35^0/7 and 36^6/7 weeks of gestation.

STUDY DESIGN

In this pre- and postimplementation retrospective cohort study, we compared late preterm infants who received placental transfusion (161 infants, DCC/UCM group) during a 2-year period after guideline implementation (postimplementation period: August 1, 2017, to July 31, 2019) to infants who had immediate cord clamping (118 infants, ICC group) born during a 2-year period before implementation (preimplementation period: August 1, 2015, to July 31, 2017).

RESULTS

The mean hematocrit after birth was significantly higher in the DCC/UCM group. Fewer infants had a hematocrit <40% after birth in the DCC/UCM group compared with the ICC group. The incidence of hyperbilirubinemia needing phototherapy, neonatal intensive care unit (NICU) admissions, or readmissions to the hospital for phototherapy was similar between the groups. Fewer infants in the DCC/UCM group were admitted to the NICU primarily for respiratory distress. Symptomatic polycythemia did not occur in either group. Median hospital length of stay was 3 days for both groups.

CONCLUSION

Placental transfusion (DCC or UCM) in late preterm infants admitted to a mother baby unit was not associated with increased incidence of hyperbilirubinemia needing phototherapy, symptomatic polycythemia, NICU admissions, or readmissions to the hospital for phototherapy.

KEY POINTS

· Placental transfusion was feasible in late preterm infants.. · Placental transfusion resulted in higher mean hematocrit after birth.. · Placental transfusion did not increase the need for phototherapy.. · Fewer admissions to the NICU for respiratory distress were noted in the placental transfusion group..

The effects of placental transfusion on mothers

OBJECTIVE

While there is ample evidence supporting delayed cord clamping (DCC) in neonates, the data on the maternal outcomes related to DCC are relatively sparse. Moreover, the outcomes, such as postpartum hemorrhage (PPH), were mostly reported for uncomplicated term vaginal deliveries. The objective of this study was to present the two primary maternal outcomes, incidence of PPH and change in hematocrit pre- and post-delivery in complex situations of preterm deliveries and term cesarean sections.

STUDY DESIGN

Maternal data were collected prospectively since the placental transfusion process was implemented in a step-wise fashion in our delivery hospitals, starting August, 2013. These data on very preterm singleton, moderate preterm, very preterm twin gestation, late preterm deliveries and term cesarean sections with DCC or umbilical cord milking (UCM) were compared with respective retrospective cohorts of deliveries in which immediate cord clamping (ICC) was performed.

RESULTS

Comparing very preterm singleton deliveries, the incidence of PPH was similar between the ICC and DCC groups (2.3% vs. 1.7%). There was no significant difference in mean hematocrit change pre- and postdelivery (3.06 ± 1.32 vs. 3.47 ± 1.52). When 45 s DCC cohort was compared with 60 s DCC cohort, there were no significant differences in the incidence of PPH (1.7% vs. 4.8%) or the hematocrit change pre- and postdelivery (3.47 ± 1.52 vs. 4.32 ± 1.88). PPH was not observed in either group when comparing retrospective ICC cohort with prospective DCC cohort with 60 s delay in very preterm twin gestation deliveries. There was no significant difference between the mean hematocrit change pre- and postdelivery (5.5 ± 3.3 vs. 5.8 ± 3.9). When moderate and early late preterm deliveries between 32° to 34⁶ weeks of gestation were compared, there were no differences between the incidence of PPH (0.9% vs. 0%) or hematocrit change pre- and postdelivery (4.2 ± 2.3 vs. 4.8 ± 2.9). Comparing late preterm deliveries between 35° and 36⁶ weeks of gestation, there was no significant difference in the incidence of PPH (13% vs. 11.4%) or the mean hematocrit change pre- and postdelivery (5.0 ± 3.0 vs. 5.1 ± 2.8). In term cesarean deliveries, the incidence of PPH was 2.2% in the retrospective ICC group and 1.4% in the prospective UCM group. There was no difference in mean hematocrit change pre- and postdelivery (5.9 ± 3.7 vs. 6.2 ± 2.8).

CONCLUSION

DCC or UCM was not associated with the increased risk for PPH or significant change in maternal hematocrit pre- and postdelivery in very preterm singleton, moderate preterm, very preterm twin gestation, late preterm deliveries and term cesarean sections.