For many premature babies, life begins in the dark, sterile environment of a hospital incubator, with little or no contact with their mother or father for weeks.
However, some lucky babies - even the tiniest, most frail "preemies" - start life nestled on the warm, comforting chest of Mom or Dad. The practice is called "Kangaroo care" and it's a growing trend in hospitals nationwide.
"We call it 'Kangaroo care' because it involves placing the premature infant on the bare chest of the parent in a position that very much resembles the way kangaroos carry their infants in the pouch," says Dr. Karen Hendricks-Munoz, director of the neonatal care program at New York University Medical Center.
Usually clad only in diapers, the babies are placed tummy down on either the mother's or father's bare chest, with their head turned at an angle that allows them to hear the parent's heartbeat.
The infants are usually left connected to the heart and respiration monitors and sometimes even the breathing tubes that help keep them alive. They can remain in this position for anywhere from one hour once or twice a day, to up to 20 hours a day if the hospital permits.
"Every hospital has their own version of 'Kangaroo care,'" Hendricks-Munoz says. "In our unit, we allow parents to 'kangaroo' as many hours of the day as they want. And we also use a variety of other environmental elements, such as light and sound, to help create an atmosphere that is very comforting to baby and parents."
Where it all began
"Kangaroo care" was created in 1983 in Bogota, Colombia, to comfort infants in an environment that was short on power and reliable medical equipment. When doctors there began noticing these babies did better than those in traditional care - mortality rates dropped from 70 percent to 30 percent - the news spread, and it wasn't long before the concept began catching on in the United States. Medical studies were soon to follow.
"So far, the research has shown that 'Kangaroo care' does have some important benefits," says Laurie Lyon, a neonatal nurse in the infants' special care unit at Johns Hopkins' Children's Center.
"Not only for the babies, but for the parents as well, most of whom are able to develop this amazing bond with their babies, starting at a very early age," she adds.
Parents who might normally feel a sense of depression and anxiety over having a baby in neonatal intensive care suddenly feel much more connected to their child when they participate in "Kangaroo care," Lyon says.
The babies are displaying some remarkable benefits as well. Research published in the journal Pediatric Nursing revealed that when "Kangaroo care" was combined with a quiet environment, preemies slept better and deeper. A second study said the babies also grew faster and became more stable - and went home sooner.
In 1998, research published in the journal Neonatal Network found that preemies who were "kangarooed" had a more stable heart rate and better respiration, and often needed less time on artificial breathing devices.
"You can actually watch the heart monitors on these babies, and see the changes soon after they are placed on the parent's chest," Lyon says.
Among the most intriguing findings: A remarkable interplay between the temperature of the mother's body and that of the baby.
Sense changes in body temperature
"From almost the moment the infant is in the 'kangaroo' position, the mother's body can sense changes in the baby's body temperature. And her body will respond accordingly, either cooling down or warming up in response to the baby's need at any given time," Hendricks-Munoz says.
A study published in the journal Heart and Lung showed that babies "kangarooed" by their fathers often needed blankets to keep them warm, while those held by their mothers did not.
While it's hard to argue with the success of "Kangaroo care," critics fear it can increase the risk of infection in children so vulnerable that almost any germ can be life-threatening.
Hendricks-Munoz and her colleagues at New York University Medical Center are studying this very possibility. So far, she says, preliminary results point to the inescapable benefits of "Kangaroo care."
"We are continuing to find that 'Kangaroo care' helps babies grow stronger and leave the hospital sooner - up to 20 days sooner - with no evidence of increased risk of infection," Hendricks-Munoz says.
(Updated November 2007 by Dr AH Walele)