The labor market has largely recovered since COVID-19 hit, but some disparities between men and women still remain.

The labor force participation rate for women in their prime working years (ages 24-54) hit a record high of 78.1% in May, according to the Bureau of Labor Statistics, a percentage point higher than the rate pre-COVID. But women's participation fell to 77.9% the following month, while there was an uptick in men's participation.

Although it may seem like a blip at first, researchers say this fluctuation is actually part of a long-running pattern: Women's participation in the labor market tends to decline during the summer, whereas the participation rate for men remains pretty consistent.

A working paper from the National Bureau of Economic Research (NBER) found that in the summer months between May and July, women's labor force participation rate dropped 1.1% on average between 1989 and 2019. That's equivalent to almost a third of the decline in the prime-age female employment rate during the Great Recession.

The researchers attribute this shift to increased demands at home. School closures, coupled with the lack of affordable childcare options, pull parents out of the workplace and into caregiver roles, a responsibility that falls disproportionately on mothers.

This summer decline often gets lost in the seasonal adjustment, but the non-adjusted data depicts a clear pattern.

“This was a pattern that was hiding in plain sight,” said Melanie Wasserman, an assistant professor at the UCLA Anderson School of Management and co-author of the NBER paper. “This is something that is visually obvious from just staring at the non-seasonally adjusted data, which is kind of remarkable.”

Caregiving demands

Data collected since 1994 from the Census Bureau's Current Population Survey showed that “taking care of house or family” was the primary explanation for the decrease in labor participation among prime-working-age women, specifically for mothers of school-age children during the summer.

“It's really hard to progress equally in the workforce with male counterparts when you're essentially doing a second and third shift job at home, caring for your family when you're not at work,” Misty Heggeness, associate professor of public affairs and economics at the University of Kansas, said.

The caregiving demand is greater for those with young children. Mothers with children under five years old had a far lower participation rate during the month of May than mothers of older children, the Brookings Institution found. And women without children had the highest overall participation rate, which saw little fluctuation during the summer.

This seasonal decline in women’s employment and hours translates into an estimated 3.3% loss in weekly earnings during the summer months, the NBER paper found. This decrease is five times larger than the decrease men experience during the same period.

Women are more likely than men to leave work during the summer across all sectors. But some of the decline can be explained by women's tendency to sort into jobs in the education sector, oftentimes due to the flexibility these jobs grant.

In other words, women with children may be selecting careers in education for their adaptable summer schedules, even at the sacrifice of pay.

"[This phenomenon] is the result of a long-standing feature of the US educational system," Wasserman said. "And so it's kind of embedded [and] deeply rooted in our society."

Verdict 'still out' on remote work

The rise of remote and hybrid work during the pandemic opened up more flexible options for parents. But it's not yet clear if remote work is leading to more equitable working arrangements.

"On the one hand, you're allowing more flexibility so both parents can potentially now take on a more involved role," Olga Stoddard, associate professor at Brigham Young University, told Yahoo Finance.

"But on the other hand, you still have these really strong gender biases and gender norms about who should be taking on the more dominant child-related or household-related role," she added. "And so allowing women to work from home could potentially exacerbate some of these existing gaps as opposed to ameliorating them. And so I think the verdict is still out whether this is a positive or negative development."

Even while working from home, women experience more child- and school-related interruptions during the day.

A recent paper found that, in two-parent households with a mother and a father, schools were more likely to contact mothers than fathers. This was the case even when the school was given the contacts for both parents.

“We're doubling down on these signals,” Stoddard said. “The household is sending a very explicit message that, look, the father wants to be involved, wants to be ... the point of contact, and yet the principals are still reverting to kind of the gender norm.”

These workday interruptions can translate into long-lasting career impacts. The NBER report found that child-related interruptions influenced women to select a career that provided more flexibility and a reduced commute but less pay or promotional opportunities.

“[Women are] not necessarily at the table when the next opportunity to lead a project happens, and missing out on leading that project could mean they miss out on the next promotion,” Heggeness said. “Inequality in the home might not seem like it's related to inequality in the workplace, but it is directly and intensely related to inequalities in the workplace today.”

While the US has made large strides toward resolving these inequities, Heggeness stressed that data on parents in the labor force could be improved. In particular, she emphasized the need for more granular data that includes parent status and the presence of caregiving pressures.

She added that the monthly jobs report, seen as a crucial look at the labor market, does not capture the full picture of employment and can lead to "erroneous conclusions."

"I definitely don't think the current statistics are sufficient to really help us understand what's happening with parents in today's economy and in today's labor market or what's happening with caregivers,” Heggeness said. “In terms of helping us really understand the dynamics of how individuals and families are thriving, it's not enough.”

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