©The Star
Dr. Cynthia Maxwell holds Graham Berry's umbilical cord moments after his delivery at Mount Sinai Hospital in Toronto last month.

A few more minutes of maternal attachment may give newborns months of significant health benefits, according to a new McMaster University study that urges doctors not to cut umbilical cords immediately after birth.

In their efforts to "tidy things up" as quickly as possible, many doctors and midwives clamp and cut off umbilical cords as soon as babies have been delivered, said McMaster researcher Eileen Hutton.

But waiting at least two minutes would allow precious red and white blood cells to be transferred to the infant from the placenta before it is expelled from the womb, says Hutton, whose study was published yesterday in the Journal of the American Medical Association.

"We really haven't given a lot of consideration in the past to the fact that there may be some value to the placenta (remaining attached)," said Hutton, an epidemiologist and assistant dean of the Hamilton school's midwifery program.

" ...The baby's born and the next thing you do is clamp the cord, and people haven't really thought about whether this is a good thing or not a good thing."

But delaying the cut could protect against anemia and irregular breathing for weeks and months after delivery, she said.

"If you increase the overall volume of blood (in the infant), you're increasing the iron stores and the number of red blood cells," Hutton said. "Also, the white blood cells, which contribute to immunities." The study could change the way babies are delivered in this country, said Dr. Donald Davis, president of the Society of Obstetricians and Gynecologists of Canada.

Umbilical cords are typically cut within 30 to 60 seconds after normal deliveries, but leaving them intact for a few minutes might benefit babies, especially those whose mothers did not eat nutritious food while pregnant.

"I don't think there would be a problem waiting two minutes and certainly there are benefits," he said. "If these babies have a little bit better iron stores, a little bit higher hemoglobin, then they're going to fare better ... their blood is going to be able to carry more oxygen to vital and growing tissues like the heart and the brain."

The society is interested in Hutton's research and, if it recommends the study's findings, delayed cord cutting could become standard procedure in Canada.

"Most certainly, the society is interested in studies like this ... and this will definitely be examined," said Davis.

The placenta, which grows attached to the wall of the uterus, is a temporary organ that allows the transfer of nutrients from mother to fetus via the umbilical cord and becomes part of the baby's circulatory system. It typically remains within the womb for several minutes after birth until continued uterine contractions expel it.

According to the study, between 25 and 60 per cent of a newborn's blood supply stays in the placenta and cord after birth. But the womb can act like a pump, moving more blood from the placenta to the infant.

"Depending on when you do the clamping, the baby will have more or less of what is, in fact, its own blood," Hutton said.

There was not enough information in the study to determine whether babies born through caesarean section would benefit equally from prolonged placental attachment.

The delay would have no negative health impacts on the mother during a normal, full-term birth. The umbilical cord is long enough in most cases that the mother can hold her infant on her stomach until it is cut.

Meanwhile, normal postnatal care of the newborn can be administered while the infant is still attached.

"It's an intervention that has the potential to have a (positive) impact on a large number of babies and at a very low cost," Hutton said. "This benefits the baby without any real down sides for mom."

The study, co-authored by University of British Columbia researchers, looked at 15 earlier papers involving almost 2,000 newborns in 11 countries.

Hutton said it gives parents the information they need to start discussing when to cut the cord with doctors before delivery.

"It's one of those areas where parents can have probably quite a large influence in terms of changing practice."