Usually when a baby is born, his or her umbilical cord is cut within a few seconds of birth. But a Swedish study suggests that waiting a few minutes to cut the cord may be linked to better motor and social skills later in childhood. This link may be stronger in boys than in girls.
Several studies have found that delaying the cutting of the cord seems to promote better health in the infant. Delaying the cutting of the cord allows the extra few ounces of blood that is in the cord to transfuse into the baby. It is known to help increase iron levels in the blood in the first few months of life. The practice of cutting the cord as soon as possible was started because it was thought to help prevent hemorrhage in the mother.
This study is a long-term follow up to an earlier study of delayed cord clamping. Babies who were born after a low-risk full-term pregnancy at a Swedish hospital were randomly assigned to have their cord cut within 10 seconds of the birth or at least 3 minutes after the birth. They were asked to return for intelligence tests and tests of motor and social skills when they were 4 years of age. At that time, 263 children were evaluated by a psychologist who did not know which group they were in.
Although there was no difference seen in intelligence for both groups of children, more children in the delayed cord cutting group had better motor skills and better skills in social domains than the others. The differences were more notable in boys then in girls.
The authors of the study theorize that delaying cutting the umbilical cord may affect the development of the nervous system by increasing the amount of iron in the body in the first few months of life.
The World Health Organization now recommends that the physician or midwife wait at least one minute after birth, or until visible pulsing stops, to clamp the umbilical cord. The American College of Obstetricians and Gynecologists advocates delayed cord clamping for premature infants, but does not believe that there is enough evidence to prove a benefit for full-term babies.
The study was published in JAMA Pediatrics.
