While there’s no doubt that raising a family is never cheap, there’s a new report that says many new mothers often tend to underestimate the financial challenges of being a working parent. In fact, there’s a new study that suggests that one of the reasons why there is a decreasing number of women in the workforce is simply because the math just doesn’t add up for them. In other words, it doesn’t make much financial sense for a mother in a two-parent household to go back to work.

The study, posted on the National Bureau of Economic Research's website, and conducted by Ilyana Kuziemko (of Princeton University), Jessica Pan (of the National University of Singapore), Jenny Shen (of Princeton University), and Ebonya Washington (of Yale University) says that when women make career-related decisions, they often underestimate how much their family life will affect their ability to work.

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In other words, women are most likely to sacrifice something in their lives, whether it’s professionally or personally-related. Working women who put in more than 40 hours of week in the office – which is often the case – will feel as though they are missing out on important moments and milestones at home with their family. And for those who put their families over their work obligations, there’s a chance that they might miss out on important deadlines, meetings, or work-related projects.

If that weren’t enough, there’s also the simple fact that new moms may not have the time or energy to work long hours, especially if they have young children at home. It also doesn’t make much financial sense for a new mother to work a full-time job in most cases.

Before heading back to the work force, many couples factor in the cost of childcare, transportation, and so on before a mom goes back to work. And more often than not, they feel as though the disadvantages outweigh the benefits, leading them to stay at home and raise their families instead of going back to work.

Long story short, the United States doesn’t make it very easy for women to return to the work force after giving birth. Many women end up having to make sacrifices, and it’s usually their career that ends up on the cutting room floor first.

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