LOS ANGELES, May 7 (Xinhua) -- Babies born to depressed mothers are more
likely to have sleep problems and early-onset depression during childhood, a new
study has found.
In the first six months of life, these babies, affected by their mothers'
depression, took longer to fall asleep at night, slept in shorter bursts and
less soundly than infants born to mothers not experiencing depression, according
to the study published in the May issue of Sleep.
Over six months starting at two weeks following birth, the researchers at the
Sleep and Chronophysiology Laboratory at the University of Michigan Depression
Center monitored the sleep of 18full-term born children and their mothers for
periods of seven consecutive days once a month.
The mothers -- some of whom had no personal or family history of depression and
others who had been diagnosed with depression or elevated depression symptoms --
also kept journals about daily sleeping and waking patterns.
Though unsure of the cause of these disruptive sleep patterns, the researchers
said they believe the condition and its consequences could be reversed in the
child.
"We do think that we could develop a behavioral and environmental intervention
to improve entertainment of sleep and circadian rhythms in the high-risk
infants," study lead author Roseanne Armitage said.
"They may still be modifiable, since brain regulation is very plastic and
responsive in childhood."
Past studies suggest that cortisol, a stress hormone produced in greater amounts
by depressed women during pregnancy and after delivery, may affect the infant's
ability to sleep.
If infant sleep problems are not addressed, they can become long-term issues
that can affect not only the child's mental and physical health, but also the
mother's, past studies have shown.
This is a particular issue among people with maternal depression. The mother's
health could further deteriorate if her child's sleep issues also cause her to
lose valuable rest time.
The latest study suggested that future studies should examine whether infant
sleep patterns can be modified and what are the best conditions for nighttime
sleep.