SUNDAY, May 1 (HealthDay News) -- Increased bursts of sleep in
infants are linked with growth spurts, new research indicates.
The new study included 23 parents who kept daily sleep records
for their infants (14 girls, nine boys), who were 12 days old at
the start of the study. The researchers analyzed the total of 5,798
daily sleep records and also tracked the infants' growth.
The infants had uneven bursts of sleep, with the amount of sleep
over a 24-hour period increasing at irregular intervals by an
average of 4.5 hours per day for two days, the study found. In
addition, the infants' number of sleep episodes per day also
increased in intermittent surges of an average of three extra naps
per day for two days.
There was a significant association between these increases in
sleep and growth spurts in body length, which tended to occur
within 48 hours of the sleep bursts. The researchers determined
that the likelihood of a growth spurt increased by about 43 percent
for each additional sleep episode and by 20 percent for each extra
hour of sleep.
The study is published in the May 1 issue of the journal
Sleep.
"The results demonstrate empirically that growth spurts not only occur during sleep but are significantly influenced by sleep," lead investigator Dr. Michelle Lampl, a professor in the department of anthropology at Emory University in Atlanta, said in a news release from the American Academy of Sleep Medicine. "Longer sleep corresponds with greater growth in body length."
The nature of the link between increased sleep and growth in
infants isn't clear, but it is known that the secretion of growth
hormone increases during sleep, Lampl said.
The findings may be helpful for parents, who can become
frustrated by the variability and unpredictability of an infant's
sleep patterns, she added.
More information
The Nemours Foundation has more about
children and sleep.