Sharon Jayson, USA TODAY
Now, new research in the journal Psychological Science find that overall, "parents (and especially fathers) report relatively higher levels of happiness, positive emotion, and meaning in life than do non-parents."
Of the three studies, the largest sample comes from 6,906 individuals collected between 1982 and 1999. It found that fathers and parents between ages 26 and 62 were happier, but not mothers, young parents and single parents. There were no differences in happiness between moms and women without children, but young parents and single parents were significantly less happy than childless peers, says co-author Sonja Lyubomirsky, a psychology professor at the University of California-Riverside.
"The effect is small, but real," says Lyubomirsky, whose book, The Myths of Happiness, was published this month.
In the second study, researchers paged 329 adults at random times over one week and asked about their feelings. They found greater well-being and more positive emotions among parents. The third study, of 186 parents with at least one child 18 or younger living at home, found more positive emotions when parents were caring for their children than when they weren't.
"It's ridiculous to compare parents of 1-year-olds to parents of 30-year-olds," Lyubomirsky says. "It's not very meaningful. You have to look at what kind of parent and what other factors are involved."
Research presented at last year's Population Association of America meeting also found parents happier. One study, which analyzed data from two nationally representative surveys, found that parents weren't as happy as non-parents from 1985 to 1995, but were happier from 1995 to 2008 - because of a decline in happiness among non-parents. Another international study followed individuals before and after having children and found happiness rose before a child's birth and right after, then dropped, but not below pre-child levels.
"Psychologists are perhaps finding different things," says sociologist Robin Simon of Wake Forest University in Winston-Salem, N.C. "There is no sociological study I'm aware of that shows parents do better than non-parents."
A published study she conducted found parents are less happy than non-parents. Now, she has worked with others on two large, not-yet-published studies that also find lower physical and mental health among parents.
"I'm absolutely confident in saying that across these large data sets, parents do not enjoy better mental and physical health than non-parents," she says. "In fact, the evidence clearly points in the opposite direction: Parents report lower levels of happiness, higher levels of depressive symptoms and assess their physical health as poorer than persons who never had children."
In one of those studies of thousands of individuals worldwide, U.S. parents reported significantly lower levels of happiness than non-parents - and lower levels than in 21 other countries. "The stress of parenthood is enormous, and it's especially stressful in the United States," she says.
Her findings also suggest kids' ages don't matter: "Parents do not do better than non-parents. Parents do worse," she says. "It's a cautionary warning: You should know what you're getting into."