(PhysOrg.com) -- The kind of job a woman has may be just as important as whether she works or not when it comes to the well-being of her child.

That's the implication of a new study by University of Michigan researcher Amy Hsin, presented today (April 30) in Detroit at the annual meeting of the Population Association of America.

"Bad jobs" have been on the rise in the United States for decades. According to one estimate, the share of U.S. labor hours spent in low-paid jobs that require little education has increased by 35 percent since 1980. And for those with less than a college education, the rise in these jobs, most in the service sector, has exceeded 53 percent.

For the study, supported by a grant from the National Institute on Child Health and Development, Hsin, a sociologist at the U-M Institute for Social Research (ISR), and colleague Christina Felfe at the University of St. Gallen (Switzerland), defined bad jobs by the amount of physical hazards and social stress involved.

They compared these rankings with occupations reported by 1,090 mothers interviewed as part of the ISR Panel Study of Income Dynamics. The researchers also had information on how much time the women spent with their children, and tests of children's verbal and math skills.

In general, the researchers found that the worse a mother's job, the worse their children did on verbal skills. But the mother's had a significant impact on how harmful a bad job was to her kids.

Bad jobs for more educated mothers were different from bad jobs for less-educated moms, they found. The most common bad jobs for mothers with high school educations were assemblers, cleaners, foremen and nurse's aides, for example, while the most common bad jobs for college graduates were registered nurses, therapists, and elementary school teachers.

Stressful jobs for more educated moms tend to pay relatively well, and Hsin believes the higher pay compensates for the higher stress mothers experience in these occupations. For less educated mothers, Hsin says, they suffer a double whammy—high stress plus low pay. This seems to intensify the negative impact on their children's behavior and reading and vocabulary skills.

Hsin and Felfe found that moms with bad jobs were spending just as much time with their children as other mothers. "This suggests that it's the quality of time mothers are spending with their children that suffers when have bad jobs," she said. "Because they've had such stressful days, they may be less patient, attentive, and responsive than they would otherwise be able to be, and this is what may be having a negative impact on their children's achievement."

What can moms do, especially in an economy where it may be necessary to take any job you can get, even a bad one?

"It's hard to expect women who are stressed out and exhausted to be able to put their feelings aside for the sake of their children," Hsin said. "In these circumstances, quality daycare may be a major help, but unless they receive some kind of aid, that is usually out of reach for women with bad jobs that don't pay well."

Provided by University of Michigan (news : web)