Jan. 6, 2011 -- Science has some new validation for all the women who have enviously eyed their slumbering husbands as they crawled out of bed in the middle of the night to tend to crying babies, sick elders, or even just to let the family pet outside.
A new study shows that women are more likely than men to give up sleep to take care of others, making gender roles a powerful reason -- beyond medical problems like depression or sleep apnea -- that women don’t get enough sleep.
“If people have problems sleeping, physicians feel they find the problem and treat it with the right drug, technology, or surgery,” says David Maume, PhD, director of the Kuntz Center for the Study of Work and Family at the University of Cincinnati, who was not involved in the study.
“But when you look at sleep as situated within our varied wake-time responsibilities, gender inequality in those daytime obligations produces gender differences in sleep. In this sense, sleep is the latest frontier in which we see gender differences in daily lives, suggesting that we are not as equal within family lives as we'd like to think,” Maume says.
Researchers at the University of Michigan studied time diaries kept by more than 20,000 working parents through the American Time Use Survey, which is conducted by the U.S. Census.
They found that women are about two-and-a-half times more likely than men to take the night shift for caregiving.
What’s more, women are typically up longer in the middle of the night than men, an average of 44 minutes compared to 30 minutes.
Perhaps most surprisingly, that sleep gap persisted even when the woman was the sole breadwinner in a couple. About 28% of women who were financially supporting their families by themselves reported getting up at night to care for others, compared to about 4% of men in the same role.
Experts say this apparent sleep disparity between the sexes could have powerful consequences for a woman’s health, her quality of life, and even her career aspirations.
“We know from biological, medical research that interrupted sleep is clearly not restful, it’s poor quality sleep. It doesn’t have the restorative benefits that we need to help support the top functioning in other realms,” says study researcher Sarah Burgard, PhD, an associate professor of epidemiology and sociology at the University of Michigan School of Public Health in Ann Arbor.
Women in their 20s and 30s, the prime childbearing years, appeared to be most affected by this sleep disparity between the sexes, a time when many women are trying to advance in their professions.
“The time when many women are having their children is actually a very important career building period, right?” Burgard asks.
“So let’s say you have primary responsibility for getting up with the kids at night and you’re doing it for several years if you have more than one child. That’s coming at a time when you need to be ‘on’ at work all day. That’s when the promotions are happening, when some really important salary building stuff is happening. That’s going to affect your salary trajectory for the rest of your life,” she says.
Understanding Why Women Are More Likely to Get Up at Night
So what’s to explain why women are more likely to be the nighttime caregivers in their households than men?
Part of the explanation may be biological. Women who are breastfeeding, for example, may be the only ones who can feed children in the middle of the night.
And a 2007 brain imaging study found that people reacted differently to a child’s cries depending on their sex and whether or not they were parents, leading scientists to wonder if men just don’t hear nighttime cries as quickly as women do.
And Burgard thinks some children may learn to prefer their mother’s attention at night, and in that way, make the choice for weary parents.
Some women may also take particular pride in claiming the role of primary caregivers in their homes, exhausting as that may be.
Sleep Important for Health
Meir Kryger, MD, the director of sleep research and education at Gaylord Hospital in Wallingford, Conn., has spent his career trying to understand gender differences in sleep.
He says many women find it a lifelong struggle to get a good night’s rest, and their health suffers for it.
“But step one is to make sleep a priority and say, ‘In order to feel good, I need to sleep well, and in order to sleep well and enough, I need to do something about it,” Kryger says. “Sometimes the doing something about it is simply saying, ‘OK, I’m only sleeping four hours a night because I’m up for two hours. I’m going to split this duty with my husband or partner, or whatever.’ In other words, start to make solutions to whatever the problem is.”
Maume agrees. He says this research could be a way for a woman to open a dialogue with her more rested partner.
“Getting sufficient sleep is an obligation we owe to ourselves so that we can be better at work and have more harmonious family lives,” Maume says. “Of course, the insight of this article is that women more than men are accountable for the needs of family members, and their sleep gets short-changed as a result. So to the extent that women define household obligations and childrearing as activities that should be shared, the more successful they will be preventing their sleep being interrupted by caregiving.”