COLUMBUS, Ohio -- New research shows that while babies born two to three months prematurely may have mild behavior and sensory response problems, most develop normal motor and mental function.
Preterm infants tend to be more active and more sensitive to touch than babies carried full-term, the study found. This may be in response to lack of time spent in the womb or to an immature central nervous system.
Past research had suggested infants born early take longer to develop necessary sensorimotor skills, which might directly affect their behavior later in life. In the current study, preterm infants differed slightly in sensory responsiveness. However, there were no significant developmental differences between preterm and full-term infants.
"Parents need to understand that while there may be some behavioral differences, chances are their preterm baby will develop normal sensory responsiveness," said Jane Case-Smith, associate professor of allied medicine at Ohio State University.
The research appears in a recent issue of the American Journal of Occupational Therapy.
The researchers looked for signs of difficult behavior and abnormal sensory responsiveness in 45 babies born more than a month early. These babies, who averaged 12.2 months old at the time of the study, spent an average of 29 weeks in the womb. Full-term babies spend nearly 40 weeks -- a full nine months -- in the womb. After birth, the preterm infants spent at least two weeks in the neonatal intensive care unit (NICU) at Children's Hospital in Columbus.
Case-Smith and her colleagues asked the primary caregivers to fill out a questionnaire about their baby's behaviors. The questionnaire measured each infant's response to touch, movement, hearing, vision and temperament. The researchers used an infant development test to assess the babies' mental and motor skills. They compared the results of the preterm group with a group of 22 full-term babies.
They found that the preterm babies had slightly lower mental development scores than the full-term control group. However mental scale scores were comparable between the groups. The premature group did have a slightly higher tendency to bite objects, to arch their backs when held, to touch others and to spin and rock while sitting.
"Premature babies seem to make up for their lack of early sensory experience in other ways," Case-Smith said. "Some of the behaviors often seen in preterm infants -- such as biting -- are appropriate sensory seeking behaviors for this age group. These behaviors may be seen more frequently in preterm infants, but they don't suggest developmental problems."
After spending the first several weeks of life in a crib at the NICU, babies born early may compensate by becoming extremely active. Caregivers, often concerned that their child tends to bite, rock, spin and move a great deal, should realize that their baby is fine.
"The preterm babies' developmental scores in the study were normal," Case-Smith said. "There was no correlation between developmental scores and sensory problems, suggesting these mild problems aren't interfering at all with development."
Case-Smith said the results do not mean that all babies born prematurely won't experience some physical or mental difficulties in the future. But much of the behavior that preterm infants exhibit during their first year does not have long term consequences for development.
These children may need to actively explore their environment, seeking movement as much and as often as they can in order to compensate for the lack of earlier sensory experiences, she said.
"Caregivers should let the babies learn and explore on their own," Case-Smith said.
Study co-authors include Linda Butcher and Diana Reed, both occupational therapists at Children's Hospital.
Contact: Jane Case-Smith, (614) 292-0357;
Case-Smith.1@osu.edu
Written by Holly Wagner, (614) 292-8310;
Wagner.235@osu.edu.
Journal
American Journal of Occupational Therapy