Cuddling up against mother's bare skin can help tiny premature babies recover more quickly from the pain of being stuck with needles and other procedures, Canadian researchers reported on Wednesday.

Babies held tightly against their mother's skin in a "kangaroo mother care" position squirmed and grimaced less than babies swaddled in blankets, the researchers found.

"Skin-to-skin contact by the mother, referred to as kangaroo mother care, has been shown to be efficacious in reducing pain in three previous studies," Celeste Johnston of McGill University School of Nursing in Montreal and her colleagues wrote in the journal BioMed Central Pediatrics.

But those studies involved older babies. Her team tested 61 preterm babies born between 28 and 31 weeks.

Such preemies spend weeks in neonatal intensive care units and are often subjected to painful medical procedures. Parents and nurses alike find it one of the most distressing things about having an infant in the unit, the researchers said.

Johnston's team assigned half the newborns to "kangaroo mother care" and half to the usual condition of being swaddled in an incubator.

"In the experimental condition, the infant was held in kangaroo mother care for 15 minutes prior to and throughout heel lance procedure," they wrote.

They measured the babies' responses using the Premature Infant Pain Profile, which measures grimacing, maximum heart rate and blood oxygen saturation levels.

"The pain response in very preterm neonates appears to be reduced by skin-to-skin maternal contact," Johnston said in a statement.

"This response is not as powerful as it is in older preterm babies, but the shorter recovery time using (kangaroo mother care) is important in helping maintain the baby's health."