CHAMPAIGN, Ill. -- For mothers of premature, very low birth-weight babies
that began life in the sterile confines of a neonatal intensive care unit,
the second year of motherhood may bring new stresses and a barely 50 percent
chance that a secure bond will form with the children, researchers report.
The findings provide new insight on how medical technology's ability to
keep increasingly younger babies alive may impact early cognitive development.
Researchers gathered information about 37 babies, who weighed an average
of 2 pounds at birth and were born 13 weeks early in the normal 40-week
gestation period.
The findings were detailed in the September issue of Developmental Psychology
by Sarah Mangelsdorf, a professor of psychology at the University of Illinois;
Jean L. McHale, a former U. of I. graduate student in psychology; and University
of Michigan researchers James Plunkett, Cynthia Dedrick, Meryl Berlin, Samuel
Meisels and Margo Dicthellmiller. Previous studies had found little difference
in the quality of parent-infant attachment between premature infants of
less risk and normal infants.
The researchers observed infant-mother interaction in homes and in a laboratory.
All of the infants had spent an average of three months in intensive care
at the University of Michigan Hospital and had survived without serious
physical or neurological complications.
Most troubling, Mangelsdorf said, was a decline in the rates of secure parent-infant
relationships in the first two years. "At 19 months, 75 percent of
normal full-term babies were rated as secure, but attachment security for
very low birth-weight babies was just under 50 percent. At 14 months, the
distributions of the two groups were about the same, but there was a shift
to insecurity at 19 months."
Based on the mothers' self-report data on the impact of the infants on their
families, Mangelsdorf theorizes that a decline of professional and informal
support after a child goes home may allow for new stresses. "The second
year may in fact be harder on the parents," she said. "Parents
tend to compare their child with others in the same age group rather than
with other premature babies; they see their child as behind developmentally.
"There is a huge variability in the outcome of these kids, but I am
struck by the remarkable resilience of the human organism," she said.
"Some of these babies were the size of your hand when they were born,
and they had been hooked up to machinery to keep them alive. Yet we later
saw them running around in the lab at 3 years of age. When my student coding
the videotapes tried to guess which kids in our sample had been premature
and which had not, her guesses were no better than chance."
Unpublished data show that while the premature infants performed significantly
lower on measures of cognitive development through age 3 than did full-term
children, they still scored in the average range. In an earlier paper, the
researchers suggested that parental education programs to increase knowledge
about child development may help parents enhance the developmental outcomes
of infants born at risk.