Babies born with a low birth weight who are regularly held by their mothers skin-to-skin — or "kangaroo style" — may have a lower risk of dying prematurely, according to a new analysis of previous research.
In the analysis, researchers looked at 124 studies that examined the relationship between so-called kangaroo mother care and health outcomes in newborns.
Newborns born at a low birth weight — less than 4.4 lbs. (2 kilograms) — who received kangaroo mother care had a 36 percent lower chance of dying prematurely, compared with low-birth-weight newborns who did not receive such care, the researchers found. Moreover, the low-birth-weight babies who received kangaroo mother care had a 47 percent lower risk of sepsis — a serious illness that occurs when the body has an overwhelming immune response to an infection — compared with those who did not receive kangaroo mother care, they found. [7 Ways Pregnant Women Affect Babies]
"While [kangaroo mother care], or skin-to-skin care, is particularly useful for low-birth-weight babies born where medical resources are limited, developed and developing countries are moving to 'normalize' [kangaroo mother care] or skin-to-skin as a beneficial practice for all newborns and mothers," Dr. Grace Chan, co-author of the analysis and an instructor at the Harvard T.H. Chan School of Public Health, said in a statement.
In 68 percent of the 124 studies included in the analysis, the authors defined kangaroo mother care as continuous and prolonged skin-to-skin contact between the newborn and the mother. In 13 percent of the studies, the authors defined it as a combination of regular skin-to-skin contact and breast-feeding. In 19 percent of the studies, kangaroo care also included an early discharge from the hospital or close follow-up, in addition to skin-to-skin contact and breast-feeding.
In 66 percent of the studies included in the analysis, the doctors who did the studies recommended less than 4 hours per day of skin-to-skin contact between the mother and the baby, and in 25 percent of the studies, the doctors recommended 22 or more hours of skin-to-skin contact a day, the researchers said. In the remaining studies, the doctors who did the studies recommended between 4 and 21 hours of skin-to-skin contact a day.
To maximize the health benefits of kangaroo mother care for babies, the World Health Organization currently recommends continuous skin-to-skin contact for as much time per day as possible, Chan said. Some data suggest that more than 22 hours per day is beneficial, but "that's really hard to do," she told Live Science. Between 8 and 12 hours probably would be helpful, Chan added.
It is not exactly clear why kangaroo mother care may be beneficial for babies' health and survival, the researchers said. One explanation could be that because the skin acts as a protective barrier against infections, and the skin of many preterm babies has not fully developed, "having the baby very close to the mother may protect the baby from coming in contact with organisms that could cause infections," Chan said.
Moreover, having the baby in close contact with the mother may allow the mother to spot signs of infection or other illness early on and thus seek medical attention sooner, Chan said.
The new analysis was published today (Dec. 22) in the journal Pediatrics.
Live Science newsletter
Stay up to date on the latest science news by signing up for our Essentials newsletter.