The following is a summary of “Umbilical cord milking in nonvigorous infants: a cluster-randomized crossover trial,” published in the FEBRUARY 2023 issue of Obstetrics and Gynecology by Katheria, et al.

For a cluster-randomized crossover trial, researchers aimed to compare the effectiveness and safety of umbilical cord milking versus early cord clamping in non-vigorous infants born at 35 to 42 weeks gestation. 

A total of 16,234 newborns were screened, and 1,780 were eligible for the study. Among those, 905 infants were assigned to umbilical cord milking, and 875 infants were assigned to early cord clamping. The study was conducted in 10 medical centers across 3 countries between January 2019 and May 2021. Informed consent was obtained from 606 families, while a waiver of consent was obtained from 523 families due to the urgency of the intervention.

The primary outcome was neonatal intensive care unit (NICU) admission frequency for predefined criteria. Of the 1,730 infants with primary outcome data for analysis (97% eligible), 872 were in the umbilical cord milking group, and 858 were in the early cord clamping group. The results showed that umbilical cord milking did not significantly reduce NICU admission for predefined criteria compared to early cord clamping (23% vs. 28%, modeled odds ratio 0.69, 95% CI 0.41-1.14). However, umbilical cord milking was associated with several secondary outcomes, including higher hemoglobin levels (modeled mean difference between umbilical cord milking and early cord clamping groups 0.68 g/dL, 95% CI 0.31-1.05), lower odds of abnormal 1-minute Apgar scores (Apgar ≤3, 30% vs. 34%, crude odds ratio 0.72, 95% CI 0.56-0.92), lower incidence of moderate-to-severe hypoxic-ischemic encephalopathy (1% vs. 3%, crude odds ratio 0.48, 95% CI 0.24-0.96), and less therapeutic hypothermia (3% vs. 4%, crude odds ratio 0.57, 95% CI 0.33-0.99). Umbilical cord milking also resulted in less delivery room cardiorespiratory support (61% vs. 71%, modeled odds ratio 0.57, 95% CI 0.33-0.99). No significant differences were observed for normal saline bolus, phototherapy, abnormal 5-minute Apgar scores (Apgar ≤6, 15.7% vs. 18.8%, crude odds ratio 0.81, 95% CI 0.62-1.06), or a serious adverse event composite of death before discharge.

In conclusion, umbilical cord milking in non-vigorous infants born at 35 to 42 weeks gestation did not reduce NICU admission for predefined criteria compared to early cord clamping. However, the intervention was feasible, safe, and superior to early cord clamping regarding higher hemoglobin levels, lower incidence of moderate-to-severe hypoxic-ischemic encephalopathy, and less therapeutic hypothermia.

Reference: ajog.org/article/S0002-9378(22)00649-4/fulltext