TUESDAY, April 17 (HealthDay News) -- Mothers with depression may behave in ways that disturb their infants' sleep, according to a new study.

Pennsylvania State University researchers conducted home visits with 45 mothers and their infants between the ages of 1 month and 2 years over 7 consecutive days to collect information about depression symptoms among the mothers and their infants' quality of sleep.

Greater amounts of sleep disruption were noted in infants whose mothers had higher levels of symptoms of depression and more worries about their infants' sleep, the researchers found.

They then investigated whether the mothers' symptoms of depression caused them to behave in ways that affected their infants' sleep, or whether infants' night awakenings led their mothers to be more depressed, perhaps because of lack of sleep.

The researchers found that it's the depression-linked behavior of mothers that interferes with infants' sleep. For example, mothers with more symptoms of depression and worries were more likely to pick up babies who were sleeping.

Mothers who are feeling depressed may seek emotional comfort by going to their infants during the night, the researchers explained. Mothers who worry excessively about their infants' well-being might respond to any infant sound in the night and move their babies into their own beds in order to ease concerns about whether their infants are hungry, thirsty and comfortable.

The study was published April 17 in the journal Child Development.

The findings help "us better understand what factors influence infants' sleep in homes in which mothers are depressed," lead author Douglas Teti, a professor of human development, psychology and pediatrics, said in a journal news release.

"Sleep problems often endure beyond early childhood and can have a negative effect on various aspects of development, including emotional, behavioral and academic functioning," Teti noted.

More information

The American Academy of Pediatrics has more about babies and sleep.