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This spring, a European study came out with the provocative conclusion that having children contributes “little to nothing” to the persistent gap in earnings between men and women.
The study caught my attention because I know the threat of earning less as a parent has had a chilling effect on people in my generation considering starting families. Last year, while I was reporting on motherhood dread in the US, young women told me they feared having kids would mean they’d be penalized in the workplace, affecting their financial security and opportunities. Meanwhile, the media does little to allay that concern: “One of the worst career moves a woman can make is to have children,” the New York Times once declared.
But while these economists found that Danish women who used in vitro fertilization experienced a large earnings penalty right after the birth of their first child, over the course of their careers, this penalty faded out. Eventually, the mothers even benefitted from a child premium compared to women who were not initially successful with IVF.
In other words, the so-called “motherhood penalty” that says women pay a price in the workplace for becoming moms might be less severe than previously thought.
“As children grow older and demand less care, we see that the mother’s earnings start to recover, with much of the immediate penalties made up 10 years after the birth of the first child,” the researchers wrote.
What makes this new European research so notable is that it relies on the same high-quality data that has informed previous studies on the motherhood penalty (including one Vox covered in 2018) but used an even broader sample and an approach the authors argue is better suited for long-term conclusions.
This wasn’t the first time I’d seen research that complicates our understanding of the motherhood penalty. After the essay on motherhood dread was published, I heard from Sharon Sassler, a Cornell University sociologist who studies relationships and gender.
She had recently published a paper on gender wage gaps in the computer science field and found that mothers in computer science actually earned more than childless women (though this “wage premium” was significantly less than what fathers earned).
“It was difficult for me to find a home for the attached article because reviewers cannot fathom that mothers might out-earn single women, though there is a growing body of evidence that [they] do,” she wrote in her email to me. “It might be selection [bias] … but given that folks have found this across disciplines suggests that the motherhood penalty really needs to be reassessed.”
I was curious about Sassler’s suggestion that moms might actually earn more and that we don’t often hear that because gatekeepers “seem to like the narrative that women are always screwed by family.”
I decided to dig into the literature, reviewing studies and talking with researchers to get a better sense of what we know. Some aspects of the motherhood penalty debate remain fuzzy and unsettled, including whether moms face a long-term disadvantage in the workplace at all.
There’s also some disagreement over what the problem is, exactly: Is it that mothers earn less than childless women? Is it that they’re earning less than fathers, or men who started their careers at a similar level? What is the social problem to address?
Amid our growing national conversation around declining birth rates and reproductive freedom, a clearer sense of the research on motherhood penalties could help policymakers answer these questions. It could also foster conditions that help more women feel secure making the choice to become parents if they want.
What we know about the motherhood penalty
Putting these unresolved questions aside for a moment, the research we have paints a different picture from the one that suggests having children is inherently a career-killer.
Though it doesn’t always make it into the media discussion, scholars know that the motherhood penalty — which past research has found averages 5 to 10 percent per child for women in their 20s and 30s — can vary significantly based on occupation, the age at which women have their first child, their marital status, their cultural background, and whether they live in an urban or rural environment.
Averages can mask a lot, too. White women tend to experience higher motherhood penalties than Black and Hispanic women, but the magnitude of the penalty has gone down significantly for all women over the last 50 years, thanks to factors such as increased educational attainment and mothers returning more quickly to work after having kids. In some fields, there’s no penalty at all.
“We shouldn’t think of child penalties as something that’s immutable or a constant,” said Henrik Kleven, a Princeton economist who has studied these dynamics closely. “It’s something that has changed over time.”
Moreover, though there’s real evidence that some women experience penalties after having kids, we don’t have very strong evidence that it’s a lasting hit. Other research suggests people may time their pregnancies to when their earnings were already flattening out.
One 2014 study found that for most women who had fewer than three children, the motherhood penalty essentially disappears, both in terms of wages and job status, once they reach their 40s and 50s. As the more recent study on Danish IVF users also showed, the context around the motherhood penalty changes when we take a longer view.
Those considering children deserve to make parenting decisions with the best information possible, including factors that could minimize or even eliminate labor market disadvantages. Finishing school before having kids, for example, is linked to lower or nonexistent motherhood penalties.
Many women would prefer to have kids while they’re younger even if that means they can’t maximize their lifetime earnings. Still, the growing body of research can help make the case for policies that mitigate the negative tradeoffs of having kids and create more family-friendly cultures in the process.
Ultimately, though, should the goal be to try and eliminate all penalties that mothers face?
Kleven, the Princeton economist, thinks it’s unrealistic and undesirable to expect no wage penalty after having kids. “It’s very natural, and I think right, that someone bears a child penalty. I don’t think we necessarily want to move to a world where we outsource all child care,” he told me. Rather, the goal, he said, should be to have “similar-sized motherhood and fatherhood penalties” — for the cost of parenting not to be so gendered.
That’s reasonable, but it’s also not the only potential aim. Women worrying about the cost of motherhood instead might care more about closing labor-market gaps through better employer support, or offsetting income penalties women face in the labor market through new tax and transfer programs, like federal paid leave and child allowances.
Theories on the motherhood penalty, explained
There are a few main explanations for the motherhood penalty.
The first theory is based on the idea that women might reduce their working hours, switch to part-time jobs, or simply reduce their effort at work once they become parents. This is the “human capital” explanation. The less you work, the less you could earn.
A second theory is that mothers might earn less because they were drawn to more flexible but lower-paying jobs. In other words, moms self-select into occupations that are less lucrative but have other advantages, such as requiring fewer hours or offering remote flexibility.
A third theory is that employers discriminate against mothers, viewing them as less dedicated and reliable. This discrimination could affect whether a woman gets hired at all, what her starting salary will be, whether she’ll be promoted, or if she’s considered for any leadership role.
The study out of Denmark has added a new wrinkle. Economists found that the Danish women successful with their first attempt at IVF earned much less than their unsuccessful counterparts the first year after giving birth, but started to recover income losses by year two, and 10 years out were earning the same amount.
Twenty-five years out, the successfully treated women were earning more on average than their unsuccessful counterparts. The researchers predict their total lifetime earnings to be 2 to 3 percent higher compared to those who were not successful. While the economists don’t have firm explanations for why, they hypothesize that it could be because mothers developed certain efficiency skills while raising young kids, or perhaps that they just weren’t out of the labor force long enough to lose critical skills and relationships.
In many other motherhood wage studies, researchers compare the wages and career trajectories before and after women become moms, in what’s known as an “event-study” approach in economics.
Kleven, whose motherhood penalty research has mostly fallen into the “event-study” category, defended his past work as a strong way to show at least short-term penalties but acknowledged that it may not be as clear for measuring long-term ones.
“We have this very simple method where we are just following men and women over time and we see these very sharp patterns in the data around childbirth and our interpretation is that we’re capturing here a causal effect of children on labor market outcomes,” he told me.
Some economists have raised concerns with the Denmark study, pointing out that women with less IVF success — those who are trying to become mothers but have not — may experience their own career setbacks due to disappointment associated with infertility. This could muddy the comparison between childless women and mothers in the labor market, since these childless women were not voluntarily childless. Indeed, past research has shown that infertility can cause “a long-run deterioration of mental health and couple stability.”
Petter Lundborg, the lead author of the Denmark study, agreed infertility anxiety could theoretically skew their results, but he told me that the data suggests mental health wasn’t a major factor and neither was divorce.
“We have this previous paper where we follow these women for 10 years and look at their mental health through the use of antidepressants and we see there’s actually very little of that going on, whereas there’s actually a slight uptick among antidepressant use for people who have kids,” he said. “But these are all small levels that could not possibly explain any of the effects we see, and the same goes for divorce.” He acknowledged the evidence on all this is “mixed.”
What the Denmark study can tell us
How useful are the Danish findings, really, for people living in other countries?
Denmark is a very progressive nation, after all, offering women one year of paid parental leave, affordable child care, and IVF under national health insurance. None of that applies to the US. People who seek IVF generally also tend to be older, further along in their careers, and typically done with their educational training. They’re people less likely to experience large penalties; their pregnancies are inherently planned ones.
All of this threatens how useful the findings might be for a wider audience. The study’s co-author, Erik Plug, said they’d like to transport their research design to other countries to compare, though few have as detailed, accessible data to mine through. (This is why so many fertility studies, even those by American scholars, use Nordic information.)
Still, the Denmark research builds on other studies that indicate that the motherhood penalty is much smaller in magnitude when women are older and have already finished their schooling.
A high-quality Nordic study that looked at women whose IUDs inadvertently failed found the labor market effects of these unplanned pregnancies were much larger for younger women and for women still enrolled in school.
“We can see unplanned pregnancies at different stages of life, and some are more costly,” Yana Gallen, the study’s lead author, told me.
Younger mothers experience this firsthand.
“The concern that having a kid too early (i.e. before hitting one’s labor market potential) will affect one’s career and lifetime earnings is based in reality,” said Matt Bruenig, the founder of the left-wing People’s Policy Project think tank.
Unless something changes in the way our society values money or distributes money, he added, more women will continue to plan to have their first child later in their reproductive years. Even if that’s not always what they really want.
Policies that could help mitigate adverse workplaces for moms
The US remains the only country in the industrialized world without federally funded paid leave, and research has long indicated that policies like universal child care and moderate-length paid leave can help mitigate motherhood penalties by helping women stay connected to the labor market. (Paid leave longer than a year, by contrast, can negatively affect women’s earnings and employment, partly due to atrophying skills and missed career opportunities, and employer bias that the mother is less committed to her job.)
Another way policymakers could address the motherhood penalty is by trying to offset whatever loss in job earnings moms may incur from taking on child-rearing.
“Maternity presents unique challenges to labor market participation and therefore earnings, but focusing solely on earnings as the relevant metric of inequality misses that societies have other ways of compensating people who face labor market disruptions,” Bruenig told me.
For low-income mothers in particular, researchers find that job turnover or having to reduce their work hours accounts for a significant amount of the motherhood penalty they experience. Low-wage jobs are typically the least likely to offer remote flexibility that makes balancing parenting with work easier, and the least likely to come with benefits like paid leave. Expanding policies like the Child Tax Credit and the Earned Income Tax Credit could help.
Continuing the cultural shift toward fathers’ contributing more domestic labor could also help reduce motherhood penalties by making it easier for women to balance their work and home duties. Federal policies that encourage both men and women to take parental leave could bolster this; Iceland and Sweden both offer 13 weeks of non-transferrable parental leave for dads, for example, and about 90 percent of new fathers there do take it.
Creating conditions for involved fatherhood in a baby’s first year of life can set egalitarian parenting patterns for a lifetime, Cecilia Machado, an economist who studies the motherhood penalty, recently told the New York Times.
Just as we all could benefit from a more nuanced conversation about motherhood penalties, so too could we gain from a more careful conversation about fatherhood penalties, where differences among subgroups also exist. In 2013, Harvard sociologist Alexandra Killewald found a positive wage boost (about 4 percent) only for fathers among those dads who were married, living with their children, and the biological parent.
Beyond public policies like child care, paid leave, and child subsidies, there could be more cultural pressure on employers and schools to help people balance their work and caregiving demands. Women recognize they could face genuine financial risks if they have children too early, but that doesn’t mean society can’t do its part to change those economic tradeoffs.
Scholars still have outstanding questions when it comes to the motherhood penalty. Gallen, the economist whose experiment looked at women with IUD failure, told me researchers have much to learn about children’s life outcomes, including life satisfaction overall. “How did the children born into all these different circumstances fare? Are they happy?” she asked. “Or do they seem like they grew up in these strained environments where everybody’s having all these difficult choices? I think that we truly don’t know the answer.”
Lundborg, the Danish study author, says he’s interested to see how their results hold up in different countries. “We do think that the evidence on long-run child penalties has been very weak, and there’s now some new evidence that challenges this notion that kids are responsible for long-run gender gaps in earnings,” he said. “If the results hold, then I think we need to find alternative explanations.”
These findings could ultimately be positive for women hoping to balance careers, financial stability, and parenthood.
“This narrative that kids are to blame for the earning gaps between males and females has been extremely strong in economics,” added Lundborg. “So yeah, let’s see what the future holds.”
