They don't call it work-life conflict for nothing.
A new study finds that nearly 3 in 10 working parents fear they could get fired because of their family responsibilities, and nearly one-fourth have bent the truth or lied about family responsibilities that might interfere with work.
The results were virtually the same for men and women, according to the survey of about 1,000 working parents with at least one child under age 18. The survey was conducted on behalf of Bright Horizons, a for-profit child-care chain, and had a margin of error of 3.1 percentage points.
It found that about 29 percent of all working parents surveyed worried that they could get fired because of family responsibilities.
Among a smaller group of parents who said they already had at least one worry about work-life conflict, close to half said they feared getting fired.
Getting the ax was the most common fear, but many parents also fretted about things like not getting promoted, not getting a raise or not getting choice projects because of family responsibilities.
About 31 percent said they had faked being sick because of family responsibilities, and about 23 percent said they had lied or bent the truth about family responsibilities that got in the way of work.
Ken Matos, senior director of research at the workplace think tank Families and Work Institute, said there are plenty of reasons why employees would fear repercussions when they have to ask for accommodations because of family needs.
"It's cultural, it's individual and it's systemic," said Matos, who was not involved in the Bright Horizons research.
Plenty of parents work for employers whose systems demand certain schedules, and they may fear they'll lose that job if they can't accommodate the company's scheduling needs. Many also have an office or company culture that does not condone making family accommodations.
In addition, he said, some people may have individual bosses who just don't see family obligations as a valid reason for missing work.
Matos said companies and managers can avoid such conflicts by not playing into what he calls the "hierarchy of needs," in which bosses get caught up in evaluating the validity of the reason an employee needs some job flexibility.
Instead, he said, employers can give all employees the same level of flexibility, and don't have to judge whether a sick child is more deserving a work-at-home day than a sick dog, or time off to run a marathon is more valuable than time off to watch a child's school play.
Under such a system, he said, "We talk about the work. We talk about the execution of projects. We don't talk about what you're doing when you're not here because that's not really relevant to the work."
—By CNBC's Allison Linn