In the first 24 hours after birth, nearly every newborn in the United States is subjected to a painful, but routine heel prick or needle stick to screen the blood for disease or rare genetic disorders.
In most cases that needle stick is administered without pain relief. But a new review of evidence suggests that breastfeeding can ease the pain of such routine newborn procedures.
"The babies who were breastfed experienced less pain, compared to not giving anything, or just swaddling them or a placebo of sterile water," said lead reviewer Prakeshkumar Shah, a neonatologist at Mount Sinai Hospital in Toronto.
Shah's team gathered data from eleven studies of more than 1,000 newborns. The trials tested the effectiveness breastfeeding and breast milk compared to sugar water or pacifier - to counter the discomfort of the babies' first blood draw.
Breastfeeding works better than no intervention or placebo to extinguish the signs of pain, but breastfeeding was about as effective as highly concentrated sugar water, the review found.
It's uncertain exactly how breastfeeding dampens pain, but the reviewers suspect that a mother's comforting presence, skin-to-skin contact, diversion of attention and the sweetness of breast milk all work together to soothe infants.
The meta-analysis appears in the current issue of The Cochrane Library, a publication of The Cochrane Collaboration, an international organization that evaluates research in all aspects of health care. Systematic reviews draw evidence-based conclusions about medical practice after considering both the content and quality of existing trials on a topic.
Whether or not a newborn is given pain relief for a one-time, routine procedure varies greatly from hospital to hospital and from one mom-and-baby unit to another, Shah said. Shah said some people don't perceive one procedure as significant enough to require pain relief.
Lawrence Gray, a University of Chicago Hospitals pediatrician, studies newborn behavior and development. He said hospitals have a lot to accomplish in the first 48 hours after birth.
"To get all those things done, a lot of things sort of happen automatically. And it's in that automaticity that babies get prodded and poked. The hospital's not a bunch of mean people. They are trying to get their stuff done, so the family can go home on time," Gray said.
The Cochrane review shows that breastfeeding is well tested as a pain-relief alternative, Gray said, and it should be offered to parents as the standard of care for newborns.
"Of course getting breastfeeding to work, as a hospital system, is much more labor-intensive than giving a baby a pacifier or swaddling the baby," he added. "You are really changing hospital culture."
The review compiles evidence from trials of babies exposed to an isolated painful procedure, and most of the data is from healthy full-term newborns. But the findings also suggest that breastfeeding is a pain-relief possibility for tiny premature babies. Preemies often have to undergo many painful procedures during their stay in the neonatal intensive care unit.
"We are looking for a natural, inexpensive, easily available approach to reduce pain in those babies," Shah said.
Repeated painful procedures can cause premature babies to suffer increases in blood pressure and heart rate, as well as lower oxygen levels, Shah said. And under stress, extremely premature newborns have a higher risk for brain hemorrhage, he said.
"Right now quite a lot of hospitals have adopted the practice of giving sugar water to those babies for analgesia. But we don't know what happens to them long term by exposing them to high concentrations of sugar." While the long-term effects aren't clear, Shah said, some short term studies have found delayed motor skills and lower neurological scores for preemies given sugar water for pain.
Breast milk has about 7 percent sugar, Shah said. But sugar water has to be highly concentrated - 20 percent to 25 percent sucrose or glucose - to provide true pain-relieving effect, he added.
"I think more research is needed on the effectiveness of breastfeeding and breast milk for those babies. What we are proposing in this review is to do further research on those sick babies that are admitted to the unit who are exposed to multiple painful procedures," Shah said.