Immediate umbilical cord milking or delayed clamping of the umbilical cord had no significant impact on maternal outcomes, but infants were significantly more likely to experience severe intraventricular hemorrhage with umbilical cord milking, according to results of two studies published in JAMA.
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“While the evidence for neonatal benefit with delayed cord clamping at term is strong, data related to maternal outcomes, particularly after cesarean delivery, are largely lacking,” wrote Stephanie E. Purisch, MD, of Columbia University Irving Medical Center, New York, and colleagues.
In a randomized trial of 113 women who underwent cesarean deliveries of singleton infants, the researchers hypothesized that maternal blood loss would be greater with delayed cord clamping (JAMA. 2019 Nov 19. doi: 10.1001/jama.2019.15995).
However, maternal blood loss, based on mean hemoglobin levels 1 day after delivery, was not significantly different between the delayed group (10.1 g/dL) and the immediate group (98 g/dL). The median time to cord clamping was 63 seconds in the delayed group and 6 seconds in the immediate group.
In addition, no significant differences occurred in 15 of 19 prespecified secondary outcomes. However, for whom data were available (18.1 g/dL vs. 16.4 g/dL; P less than .001).
The results were limited by factors including lack of generalizability to other situations such as emergency or preterm deliveries and by the lack of a definition of a “clinically important postoperative hemoglobin change,” the researchers noted. However, the results show no significant impact of umbilical cord management on maternal hemoglobin in the study population.
In another study published in JAMA, Anup Katheria, MD, of Sharp Mary Birch Hospital for Women & Newborns, San Diego, and colleagues found no significant difference in rates of a composite outcome of death or severe intraventricular hemorrhage among infants randomized to umbilical cord milking (12%) vs. delayed umbilical cord clamping (8%). However, immediate umbilical cord milking was significantly associated with a higher rate of intraventricular hemorrhage alone, compared with delayed clamping (8% vs. 3%), and this signal of risk prompted the researchers to terminate the study earlier than intended.
The researchers randomized 474 infants born at less than 32 weeks’ gestation to umbilical cord milking or delayed umbilical cord clamping (JAMA. 2019 Nov 19. doi: 10.1001/jama.2019.16004). The study was conducted at six sites in the United States and one site each in Ireland, Germany, and Canada between June 2017 and September 2018. “Because of the importance of long-term neurodevelopment, all surviving infants will be followed up to determine developmental outcomes at 22 to 26 months’ corrected gestational age,” they said.
The study was terminated early, which prevents definitive conclusions, the researchers noted, but a new study has been approved to compare umbilical cord milking with delayed umbilical cord clamping in infants of 30-32 weeks’ gestational age, they said.
“Although the safety of placental transfusion for the mother seems well established, it remains unclear which method of providing placental transfusion is best for the infant: delayed clamping and cutting the cord or milking the intact cord. The latter provides a transfusion more rapidly, which may facilitate initiation of resuscitation when needed,” Heike Rabe, MD, of the University of Sussex, Brighton, and Ola Andersson, PhD, of Lund (Sweden) University, wrote in an editorial accompanying the two studies (JAMA. 2019 Nov 19;322:1864-5. doi: 10.1001/jama.2019.16003).
The 8% incidence of severe intraventricular hemorrhage in the umbilical milking group in the study by Katheria and colleagues was higher than the 5.2% in a recent Cochrane review, but the 3% incidence of severe intraventricular hemorrhage in the delayed group was lower than the 4.5% in the Cochrane review, they said.
“Umbilical cord milking has been used in many hospitals without an increase in intraventricular hemorrhage being observed,” they noted.
“The study by Purisch et al. demonstrated the safety of delayed cord clamping for mothers delivering by cesarean at term,” the editorialists wrote. Studies are underway to identify the best techniques for cord clamping, they said.
“In the meantime, clinicians should follow the World Health Organization recommendation to delay cord clamping and cutting for 1 to 3 minutes for term infants and for at least 60 seconds for preterm infants to prevent iron deficiency and potentially enable more premature infants to survive,” they concluded.
Dr. Purisch received funding from the Maternal-Fetal Medicine Fellow Research Fund for the first study. Coauthor Cynthia Gyamfi-Bannerman, MD, reported receiving grants from the Eunice Kennedy Shriver National Institute of Child Health and Human Development and the Society for Maternal-Fetal Medicine/AMAG Pharmaceuticals, and personal fees from Sera Prognostics outside the submitted work. The second study was supported by NICHD in a grant to Dr. Katheria, who had no financial conflicts to disclose. Coauthor Gary Cutter, PhD, had numerous ties to pharmaceutical companies. The editorialists had no financial conflicts to disclose.
SOURCES: Purisch SE et al. JAMA. 2019 Nov 19. doi: 10.1001/jama.2019.15995; Katheria A et al. JAMA. 2019 Nov 19. doi: 10.1001/jama.2019.16004; Rabe H and Andersson O. JAMA. 2019 Nov 19; 322:1864-5.