From the press release (Marketwatch) [1]:
"Most women don't realize it, but an important factor in a woman's career choice is how easy or difficult it is to find a husband," said Durante. "When a woman's dating prospects look bleak -- as is the case when there are few available men -- she is much more likely to delay starting a family and instead seek a career."
In one study, the researchers examined the ratio of single men to single women in each U.S. state and Washington D.C. They found that as bachelors became scarce, the percentage of women in high-paying careers increased, women delayed having children, and had fewer kids when they finally decided to start a family.
In another study on college campuses, the researchers led women to believe that there were either more men or less men on campus by having participants read one of two news articles about the student population. When women read that there were fewer men than women on campus, they became more motivated to pursue ambitious careers rather than start a family.
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"Sex Ratio and Women's Career Choice: Does a Scarcity of Men Lead Women to Choose Briefcase Over Baby?" was published in the Journal of Personality and Social Psychology. Durante and Griskevicius's coauthors include the University of Minnesota's Jeffry A. Simpson and Stephanie M. Cantu and Joshua M. Tybur (VU University Amsterdam).