Recent evidence finds that delaying cutting or clamping the umbilical cord may help infants developmentally.

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More evidence finds that delayed cord clamping can help infants. Getty Images

After a baby makes its big entrance into the world, there’s a practical matter to attend to: Clamping and cutting the umbilical cord.

But this stops the flow of nutrient-rich blood from the placenta.

It’s currently common practice to clamp the umbilical cord quickly after birth, but recent research may change that.

A new study has found that delaying cord clamping after birth by five minutes can have positive effects on the brain structure of newborn infants. The study, published in The Journal of Pediatrics, was conducted by researchers at the University of Rhode Island and Brown University, and examined 73 healthy babies.

The study joins growing research that may change how babies are brought into this world.

As they were born, the researchers divided the babies into two groups. One group had their umbilical cords clamped after a five-minute delay, while umbilical cords in the other group were clamped quickly, within 20 seconds. Both groups were held on their mothers’ bare skin while the clamping took place.

When the babies were 4-months old, they were given a series of tests: a magnetic resonance imaging scan (MRI) of their brains, a test of their brain development, and a blood test that checked their ferritin levels.

Ferritin is the main storage protein for iron in the body, and ferritin tests show how much iron is currently circulating in your blood.

And the babies who’d been given a cord-clamping delay showed some pretty impressive differences.

For one, they had higher levels of ferritin in their blood than the babies who’d been clamped rapidly after birth. For another, their MRIs showed that their brains had more of a substance called myelin.

Researchers behind the study believe these two things are linked.

Myelin is a fatty substance that insulates nerves and helps them communicate efficiently. It makes up a large portion of the “white matter” of our brains, and works to protect our “grey matter,” or neural cells.

Without it, nerve messages can go haywire. There’s a category of illnesses known as demyelinating diseases, including multiple sclerosis, in which myelin gradually degrades. Without its fatty protection, nerve cells develop injuries and scars.

Dr. Mitchell Kramer, chairman of theDepartment of Obstetrics and Gynecology at Huntington Hospital in Long Island, New York, explained the importance of myelin and ferritin.

“The reason these factors were chosen to be studied is that they are linked to cognitive, motor, social-emotional, and behavioral development,” said Kramer, who was not involved in the study. “The higher the ferritin blood levels are and the more myelin content there is in brain tissue, the better the outcome of those important developmental factors.”

Kramer did say more research was needed to verify these findings and ensure it is safe for infant and mother.

Delayed cord clamping, said the researchers in the study, causes a flood of iron-rich blood from the placenta, and that in turn appears to boost myelin levels.

They believe the link is a type of cell called oligodendrocytes, cells that produce myelin in the brain and are fueled by iron.

In babies who’ve had delayed cord clamping, the extra dose of iron from the placenta may spur oligodendrocytes to produce more myelin.

“We stumbled upon the fact that oligodendrocytes require iron to do their job,” Debra Erickson-Owens, PhD, associate professor at University of Rhode Island, and lead author of the study, told Healthline. “We formed the hypothesis that a more robust ferritin level might mean there was more iron availability to oligodendrocytes.”

There could be additional explanations for this boost. Pediatric specialists Dr. Raghavendra Rao and Dr. Reeta Bora, responding to the findings in The Journal of Pediatrics, explained that the blood in the umbilical cord also contains stem cells, which could transform into oligodendrocytes and trigger more myelin growth.

The study finds that the way the umbilical cord is clamped could potentially impact the brain development of the child.

Dr. William Walsh, professor of pediatrics at Vanderbilt University, who was not involved in the study, explained the importance of the umbilical cord.

“The benefit to brain development shown in the study could also be stem cells,” he told Healthline. “The umbilical cord contains millions of important stem cells. It’s obvious that babies receive more iron from delayed cord clamping, but the explanation may be more complex.”

However it occurred, the myelin boost shown in the study is significant. Myelin levels build while we’re small; the study pointed out that we usually have 80 percent of our adult myelin levels by the time we’re two. The babies showed particularly high myelin levels in areas of the brain associated with early neurological development, like the brain stem and the parietal and occipital lobes.

While both groups of babies performed the same in tests of their learning ability and motor function, the babies in the delayed cord-cutting group might have an advantage when it comes to white matter development — though it may not kick in for a while.

Research by a Swedish team of researchers led by Ola Andersson, Professor Erickson-Owens told Healthline, “didn’t see any difference in neuro-developmental testing until the kids were 4 years of age.”

Delayed cord-clamping has been gaining increased attention for a while, but the precise length of time to wait isn’t set in stone.

The World Health Organization currently recommends clamping the umbilical cord between one and three minutes after birth, “for improved maternal and infant health and nutrition outcomes,” while the American College of Obstetricians and Gynecologists recommends clamping within 30 to 60 seconds.

ACOG also notes in its 2018 guidelines that there is a “small increase” in the rate of jaundice in full-term newborns who have delayed cord-clamping.

Erickson-Owens hopes the new evidence will create a five-minute guideline for cutting the cord.

“We found that even two minutes wasn’t enough,” she told Healthline. “We would love this to be translated into practice.”