In most hospitals, a newborn’s umbilical cord is clamped within 15-20 seconds after birth. Doctors do this to lessen the possibility of hemorrhaging for the mother. But a review of studies has found that delaying clamping of the cord just a little longer is very beneficial for the baby, and does not appear to increase the risk of severe bleeding (or other complications) for the mother.
The review, published online recently in the Cochrane Database of Systematic Reviews, found that delaying cord-clamping for at least one minute after birth greatly improves iron and hemoglobin levels in newborns (hemoglobin is the protein in red blood cells that carries oxygen to all the tissues and organs; more iron means more hemoglobin will be made). Delaying clamping of the cord allows more blood and its iron to pulsate from the placenta and umbilical cord into the baby.
Newborns whose clamping was delayed had higher hemoglobin levels 24 to 48 hours after being born; they were also less likely to be deficient in iron 3 to 6 months after birth than babies whose cords were clamped right after birth.
Previous studies of full-term newborns have shown that about 80 mL of blood, or 2.7 ounces, are transferred from the placenta into the baby by one minute after birth. Being that a term newborn only has about 8 ounces of blood in its body, 2.7 ounces represent one-third of the blood that the baby has at birth. That would explain why babies who participated in the randomized studies and had delayed cord-clamping averaged higher weights than babies whose cords were clamped early. Many doctors believe that the additional iron from delayed cord-clamping, combined with the iron stores present at birth in a full-term baby, can help prevent iron deficiency during the first year of life, a time when iron supplementation is often necessary.
The timing of cord-clamping has been controversial for years. Some decades ago, doctors didn’t rush to clamp the cord immediately after birth, and might have even waited a few minutes. But studies done in Sweden, the United States and Canada were thought to indicate that more than 90 percent of blood volume was achieved in the infant within its first few breaths. Because of these findings, and in the absence of specific recommendations as to what the best time for cord-clamping was, doctors began clamping cords sooner and sooner.
The World Health Organization currently recommends clamping the cord between 1 and 3 minutes after birth, due to the increased transfer of iron into the baby. However, an American College of Obstetricians and Gynecologists committee recently examined much of the same data included in the new review, and it concluded that there isn’t enough evidence to confirm or disprove the potential benefits of delayed cord-clamping in full-term infants. Therefore, ACOG’s position is that cord-clamping should continue to be done right after birth.
ACOG cited a 2 percent greater risk of jaundice in newborns whose cords are clamped after one minute, compared to babies who are clamped right after birth. A newborn can in fact get an oversupply of blood when the cord is clamped several minutes after birth, which can overwhelm the liver, leading to the increased risk of jaundice. (Jaundice is a condition that more than half of all newborns develop shortly after birth. It occurs for different reasons and sometimes goes away on its own; it can also be eliminated through neonatal “phototherapy.” The possibility of jaundice is one reason why all newborns are examined by a physician several days after birth.)
Another reason that American doctors hesitate to recommend late clamping for all newborns is that there are cases when the baby needs immediate care, such as when resuscitation is required or when the baby takes in meconium (baby’s first stool). In addition, in cases where a caesarian section is performed, waiting to clamp the cord could increase the risk of maternal hemorrhage.
Aside from exceptions like those, some American doctors believe that waiting 30-60 seconds before clamping the cord in healthy, full-term newborns is advisable, and that it will be good for the baby and will not pose risks for mom.
What Is the Best Position for Newborn While Waiting for Umbilical Cord to Be Clamped?
The usual procedure is to place infant at or below the level of the placenta; but this position can be awkward. A recent study from Argentina found that just as much blood is transferred when the baby is placed on the mother’s chest as when infant is placed at or below placenta level.
By Marc Courtiol