A handful of studies have suggested that breastfed newborns feed for shorter periods and wake up more frequently during the night than babies given formula. So it's been widely assumed that moms who breastfeed get less sleep than their bottle-wielding counterparts.
A study published in the journal Pediatrics, however, found that the feeding method doesn't make much of a difference on the mother's overall quantity and quality of sleep. "We thought this was too important an issue just to leave up to assumptions and so we wanted to test it empirically," explained the lead author of the study, Hawley Montgomery-Downs of West Virginia University.
The research team recruited 80 mothers who were either breast- or bottle-feeding, or using a combination of both methods. At two weeks after giving birth, the women were asked to keep sleep records and wear electronic devices that measured their total sleep for eight weeks.
"We can say there were no differences in the amount of sleep they had," said Dr. Montgomery-Downs. And even if breastfeeding moms are awoken more frequently, lactation boosts the body's production of prolactin - a hormone that facilitates sleep, she said. That suggests, after a nocturnal feeding, it should be easier for them to drift back to sleep.
"There is really no evidence to support the idea that a woman is going to get better sleep, or more sleep, if she stops breastfeeding or never starts."