Mothers who reported sleeping five hours or less per day when their babies were six months old had a threefold higher risk for substantial weight retention (11 pounds or more) at their baby's first birthday than moms who slept seven hours per day, according to a new study by Kaiser Permanente and Harvard Medical School / Harvard Pilgrim Health Care.
The study, published in the November issue of the American Journal of Epidemiology, is the first to look at the impact of sleep deprivation on postpartum weight retention. Previous studies have looked at the effect of early postpartum sleep deprivation on mothers' cognitive and emotional health but never associated weight gain.
“We've known for some time that sleep deprivation is associated with weight gain and obesity in the general population, but this study shows that getting enough sleep – even just two hours more – may be as important as a healthy diet and exercise for new mothers to return to their pre-pregnancy weight,” said Erica P. Gunderson, PhD, an investigator at the Kaiser Permanente Division of Research in Oakland and the lead author of the study.
The study also found that mothers who slept fewer hours at one year postpartum than they did at six months postpartum had twice the risk of substantial weight retention. Other studies have shown that persistent sleep deprivation causes hormonal changes that may stimulate appetite. Shorter sleep duration has not only been linked to obesity in women, but coronary artery disease and diabetes as well.
“With the results of this study, new mothers must be wondering, ‘How can I get more sleep for both me and my baby?' Our team is working on new studies to answer this important question,” said Matthew W. Gillman, MD, SM, Department of Ambulatory Care and Prevention, Harvard Medical School/Harvard Pilgrim Health Care.