A recent study suggests that umbilical cord milking, a method used to move blood from the umbilical cord into newborns who are limp, pale, and have minimal breathing, does not increase the risk of neurodevelopmental delays. The findings were published in the journal JAMA Network Open.
The study involved nearly 1,000 full-term and near-term infants. Researchers compared umbilical cord milking to the early clamping and cutting of the cord, which is done to begin resuscitation efforts as quickly as possible.
The study was conducted in response to earlier concerns that umbilical cord milking might increase the risk of brain injury in extremely preterm infants. However, the current results indicate that umbilical cord milking is unlikely to increase the risk of brain injury in term infants. This provides evidence that umbilical cord milking is a safe alternative for moving blood into a term infant’s body when there isn’t time to wait for blood to enter naturally.
Non-vigorous infants are at risk for complications such as low oxygen levels in the brain, cerebral palsy, and stroke. The standard practice for these infants is to immediately clamp and cut the umbilical cord to begin resuscitation.
For vigorous, full-term infants, the current recommendation is to delay clamping and cutting the umbilical cord for at least 30 to 60 seconds after birth. This allows blood from the cord to enter the newborn’s circulation, leading to higher levels of hemoglobin and iron compared to infants who undergo immediate cord clamping.
In the current study, the researchers evaluated children from a previous study using neurocognitive development screening tests before the children reached 2 years of age. During the previous study, providers milked 20 centimeters of the cord for two seconds, repeating this procedure three times.
Of the surviving infants in the current study, 964 were evaluated using the Ages and Stages Questionnaire-3, a developmental screening tool. The 502 children in the umbilical cord milking group had scores ranging from 225 to 280, similar to the 469 children in the early cord clamping group, whose scores ranged from 230 to 280.
Additionally, 927 surviving children were assessed for autism spectrum disorder (ASD) risk using the Modified Checklist for Autism in Toddlers, Revised with Follow-Up. The proportions of children scoring with medium-to-high risk for ASD were similar in both groups: 45 of 486 in the umbilical cord milking group and 37 of 441 in the early cord clamping group.
The previous study found that non-vigorous infants who underwent umbilical cord milking were less likely to need heart and respiratory support, had higher levels of oxygen and blood in the brain, and had higher hemoglobin levels compared to those who had early cord clamping. A follow-up study indicated that these infants also had increased blood pumped from the heart and more blood flow to the lungs and brain.
The researchers concluded that, combined with the benefits seen in their previous studies, umbilical cord milking is a reasonable intervention that does not increase the risk of neurodevelopmental delays in non-vigorous full-term and near-term infants.
The study was led by Dr. Anup Katheria of the Sharp Mary Birch Hospital for Women and Newborns in San Diego, along with colleagues from institutions in the United States, Canada, and Poland.
