MELISSA BLOCK, Host:
Sleep is an issue for all new moms. And research out today suggests there's one more reason it's important to get enough of it.
NPR's Allison Aubrey reports on the connection between shuteye and losing bad baby weight.
ALLISON AUBREY: If you ask new moms how much sleep they need to function, many will say that five hours a night is at least enough to make you feel human.
PAM GAR: Sleep is sort of the Holy Grail for new moms, I think, and dads, I guess, but it tends upon the mom.
AUBREY: Mother Pam Gar who we met up with as she strolled her daughter Roselynn(ph) says she needs more than five hours.
GAR: Oh, I think, six or seven hours is really what I need, definitely.
AUBREY: So when you get five, you feel like what?
GAR: I just feel little fuzzy and tired and not as much patience, definitely.
AUBREY: These drawbacks of too little sleep are well documented, but scientists now have evidence that lack of sleep makes it harder to take off the baby weight after a woman gives birth, much harder for many.
TRACY FLANAGAN: This is the first time it's really been shown.
AUBREY: Obstetrician Tracy Flanagan is director of Women's Health at Northern California's Kaiser Permanente. She explains the new study of almost 1,000 mothers found that those who were sleeping only five hours or less when their babies were six months old were much more likely to retain baby weight compared to women sleeping seven hours per night.
FLANAGAN: The difference is two hours, which doesn't sound like a lot of sleep difference, made the substantial impact on whether women could shed their weight.
AUBREY: In the study, many women who were getting the seven hours of sleep were able to get back down to within a pound or two of their pre-pregnancy weight by the time of their baby's first birthdays. In contrast, the more sleep deprived moms were three times as likely to hang on to 11 pounds or more of their baby weight.
Harvard Medical School's Matthew Gillman who is one author of the study says this amount of extra weight is concerning, especially since many women carry it right around the belly.
MATTHEW GILLMAN: So more of the apple-shaped and the pear-shaped and they wind up having, for example, lower HDL cholesterol levels, which is a risk factor for heart disease, so that's why it's important for the long term for women to try to retain as little weight after pregnancy as possible.
AUBREY: The study found there's weight-sleep correlation held up for both first time moms and in women who had more than one child. And Gillman says the finding fit with a growing body of evidence that suggest sleep and obesity are related throughout life.
GILLMAN: What some experimental studies are showing is that the less sleep one gets, the more the body puts out hormones that tend to increase the weight.
AUBREY: Hormones like ghrelin that can signal hunger and make people want to eat more. The findings of this weight-sleep study have so impressed obstetrician Tracy Flanagan. She says she's going to change her spiel.
FLANAGAN: I think it's significant enough that I might say to my patients more emphatically to really seek out ways to get more sleep.
AUBREY: One strategy, say experts, is to scale down late night activities, if that's possible. Mother Pam Gar who has managed to take off her baby weight says she uses evenings to cross things off her to-do list.
GAR: Oh, I tend to answer e-mails, sometimes I clean the kitchen if it's really a mess.
AUBREY: A task she'd gladly handover to someone else, but it seems multitasking and mothering go hand in hand.
Allison Aubrey, NPR News, Washington.