Although federal law prohibits employers from demoting or firing women due to pregnancy, allegations of such conduct are common. (Photo: Shutterstock)

The push for paid maternity leave has traditionally been cast as a way to support women's ability to raise families and pursue careers. But even the most generous maternity leave policies don't completely eliminate the challenge that motherhood poses to a woman's career. In some cases, they may even exacerbate them.

In Denmark, for instance, research shows that women's earnings match men up until childbirth, after which a sharp disparity emerges. The country's current leave policy provides mothers with 18 weeks of paid leave and fathers with two weeks of paid leave after the birth of a child. Parents are allowed to split the remaining 32 weeks of paid leave as they wish. In the great majority of families, it's the mother who takes most of that leave.

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The more leave that women take, either due to policies or tradition, the greater the risk that employers will avoid putting women in leadership positions. Women also fall behind simply by being out of the office for such a long period of time.

Norway has sought to combat that problem by mandating that families split parental leave between mothers and fathers. Meanwhile, in the U.S., more and more companies have begun to offer gender-neutral parental leave.

Although federal law prohibits employers from demoting or firing women due to pregnancy, allegations of such conduct are common. The Equal Employment Opportunity Commission has filed 148 lawsuits against employers relating to pregnancy bias in the past decade. In most cases, the suit alleges a woman was fired after disclosing a pregnancy.

Earlier this year a sales executive with BMF Media Group sued her employer, claiming that her pregnancy prompted the company to withdraw a recent promotion. The suit was settled and neither side would respond to questions from the Wall Street Journal.

Some employers, however, are encouraging pregnant women to move up in the ranks. Etsy says that it has hired or promoted 40 pregnant women since 2013. The Journal reports that IBM executive Alarice Lonergan received a promotion in 2015 shortly before giving birth and that she was promoted again to partner in 2018 before another birth. In both instances, Lonergran took more than three months of paid leave.

Read more: 

• JPMorgan settles parental leave discrimination suit for record $5 million
• 10 ways employers are becoming more family-friendly
• Employer in court over FMLA, maternity leave misunderstanding