BlackRock suggests women can help bolster their nest egg by exhibiting positive financial behaviors.
Among those investors who are hitting their retirement savings goals—those who have accumulated more than five times the savings of the average American woman ($112,500 compared with $21,200)—82 percent indicated they make retirement a financial priority, they are more likely to invest in stocks than the U.S. average (21 percent vs. 14 percent), and they hold less cash (57 percent vs. 68 percent).
They are also twice as likely as the average American to seek advice from a professional financial advisor.
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"A lot of women who never get help fall behind on their savings because they are not invested properly," said Curtis, noting men are not immune from poor financial decisions, either. "Men may be less fearful of risk, but anecdotally I know they also sometimes invest too aggressively. They think they can beat the market."
While women tend to err on the side of caution, she said, "they are also probably smarter in the long run about investments because they understand that slow and steady wins the race."
—By Shelly Schwartz, special to CNBC.com