Waiting to Cut Umbilical Cord
May Improve Preemies' Health
For nine months, the umbilical cord
is a lifeline between mother and baby, sending oxygenated blood
to the growing fetus. Once the baby is born, however, that connection
is often quickly severed.
But, in the case of premature infants,
a new review of past studies suggests that waiting as little as
30 seconds to cut that cord can make a dramatic difference in
the health of a newborn.
The review, which appears in the
October issue of the Cochrane Collaboration, also found
that delaying the clamping of the umbilical cord for up to 120
seconds in premature infants can lead to an increased number of
red blood cells, the need for fewer transfusions due to anemia
or low blood pressure, and a decreased risk of bleeding in the
"A slight delay in cord clamping
for preterm infants is beneficial with regard to better blood
pressure after birth, less need of blood transfusion in the first
weeks of life and less incidence of severe intra-ventricular hemorrhage,"
said the review's author, Dr. Heike Rabe, a consultant neonatologist
at Brighton & Sussex University Hospitals in Great Britain.
An infant is considered preterm
or premature if born before 37 weeks' gestation. About one in
10 babies in the United States is born prematurely, according
to the National Institutes of Health. Some of the biggest problems
premature infants face are respiratory distress, bleeding in the
brain and feeding problems.
The reason that waiting to clamp
the umbilical cord can make a difference in a baby's health is
because the delay allows blood to return from the umbilical cord
back to the baby, which can help keep blood pressure normal and
keep the red blood cell count up, the research found.
On the other hand, waiting too
long to clamp the umbilical cord can cause the red blood cell
count to rise too high, which thickens the blood. And, since respiratory
problems are common in premature infants, delaying clamping the
cord may cause a delay in treating respiratory distress.
The current review included seven
studies with a total of 297 infants born prematurely.
Clamping times varied in the studies
between 30 and 120 seconds, according to Rabe. While it's not
clear what the optimum time for cord clamping is based on current
studies, 120 seconds is the maximum time before clamping a preterm
infant, said Rabe.
Rabe and the other reviewers concluded
that waiting 30 to 120 seconds before clamping the umbilical cord
in preterm infants is associated with less bleeding in the brain
and a reduced need for transfusions.
"This study seems to make
good sense. We know that the amount of blood has a direct influence
on blood pressure and that blood pressure has an influence on
bleeding on the brain," said Dr. James Pelegano. He is director
of neonatology at Maimonides Medical Center and Lutheran Medical
Center in New York City.
Pelegano said it's often standard
practice to clamp off the cord immediately so that breathing and
other problems can be dealt with immediately. He said there's
no way to make a blanket statement that all babies should have
a delay before the umbilical cord is clamped.
"It has to be done on a case-by-case
basis," said Pelegano. "It's better if you don't have
to clamp quickly, but you don't always have that option."
But, he added, "In a situation
where the baby is not at risk from respiratory problems, delaying
cord clamping up to 30 seconds can have a benefit."
Another study in the October issue
of the Cochrane Collaboration looked at another important
issue in newborn care -- pain relief during circumcision. A review
of nearly 2,000 babies from 35 different studies found that topical
or injected pain medications appeared to help reduce the pain
of circumcision significantly. Oral pain relievers, sugar water
and playing comforting music had little effect on the babies'
response to circumcision pain.
Unfortunately, the researchers
concluded that no method was able to completely eliminate the
infants' responses to pain.
To learn more about premature infants,
visit the National
Library of Medicine.
Reference Source 101
October 19, 2004