Women now account for half the nation’s working-age population, but only 43% of full-time workers.

One reason for that is what happens when they have young children. Only about two-thirds of moms with kids under 6 work full-time, versus more than three-quarters of moms whose youngest child is between 6 and 17.

Working while balancing the demands of motherhood isn’t easy. Things that come along with children – like night-time feedings, diaper changes and mountains of laundry – are time-consuming to do yourself and expensive to pay someone else to do.

We have spent decades studying how American families spend their time, why some families are more prone to economic hardship and which policies help families thrive. We teamed up to see whether mothers in states with relatively lower child care costs are more likely than others to be employed once they have children.

State differences

U.S. families typically pay the full cost of day care, preschool and programs that take care of children before and after school. These services are expensive everywhere, but the tab is dramatically higher in some places.

In states like California and Washington, child care tends to cost more and school days are shorter on average. That increases the time or money families must spend on care.

Child care is among the largest expenses that gobble up U.S. family budgets. In New York City, it costs three times as much as tuition at an in-state public college or university.

Less time at work

We looked at mothers’ employment and childcare time across U.S. states, analyzing data the government collected for 37,993 mothers between 2005 and 2014 to compare their odds of working full-time or part-time during this decade.

We found that mothers are more likely to be full-time employees in states where child care is more affordable. In states with more expensive child care, more mothers worked part-time.

We also found mothers spent more time caring for children in states where child care was more expensive and as child care costs rose over this decade.

We believe this means families respond to rising care costs by using less of it, at the expense of mothers’ employment and careers.

While fathers today are taking a more active role in parenting, and a growing number are the primary caregivers for their kids, 93.3% of dads have full-time jobs, compared to 71.5% of mothers.

Women still do three times as much housework and a much larger share of their family’s child care than men, even when they work full-time outside the home.

Public preschools

Washington, D.C.‘s public schools offer two years of full-time preschool at no cost. In 2017, 90% of the city’s four-year-olds and 70% of the city’s three-year-olds were enrolled in the program.

Within seven years of this program’s 2009 rollout, the rate of mothers with schoolchildren who were employed increased by more than 10 percentage points.

New York City made preschool available at no cost through the public schools for four-year-olds in 2014. The program is expected to expand in 2021 to include all three-year-olds.

After school

Many families figure that once their kids enter kindergarten, stay-at-home moms and dads can easily return to work without straining the family budget to pay for child care.

That’s not always true, partly because school days rarely match work schedules. This mismatch varies to some degree because states mandate different minimum lengths for school days. In addition, some public school systems don’t mandate compulsory full-day kindergarten.

Even in states with the longest school days, children stay in school for only seven hours. That falls short of standard eight-hour workdays plus commuting time.

The mismatch between workdays and school days makes synchronizing work and family schedules extremely difficult. It also means many Americans are paying for caregivers before and after school. Others rely on relatives and friends.

We found that mothers are more likely to work part-time in communities where school days are shorter. As school days lengthen, the odds of mothers in that community working full-time rise.

Interestingly, we found that many states where child care costs more also tend to have shorter school days. That means parents can face more than one larger-than-average child care burden, depending on where they live.

All states are not equal

It surprised us to see that some states with shorter school days and more expensive child care happen to have progressive political leadership. For example, the nearly 40 million people living in California have some of the highest average child care costs, shortest school days and lowest rates of maternal full-time employment in the nation.

In contrast, we found that Nebraska has some of the most affordable child care, longest school days and highest rates of maternal employment. In Nebraska, an average of 60% of mothers work full-time, compared to 40% in California.

And thanks to Nebraska’s bipartisan support for child care spending, that state leads the nation in child care quality as well.

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Leah Ruppanner receives funding from the Australian Research Council.

Liana C. Sayer receives funding from The Eunice Kennedy Shriver National Institute of Child Health and Human Development

Stephanie Moller receives funding from the National Science Foundation.