Women are more educated, accomplished and empowered than ever before. But when it comes to married women investing and managing their money, it feels like we're stuck in the 1950s.

A new report from UBS found that 56% of married women leave investment and long-term financial planning decisions to their husbands, and 85% of women who defer to their husbands believe their spouses know more about financial matters.

It's not just older generations. Millennial women are more likely to leave investment decisions to their husbands than any other age group, based on the report, which included surveys with nearly 1,700 married couples, including heterosexual and same-sex couples.

Here's why these numbers are a concern: Women are living longer than men. The average life expectancy for a woman is five years more than a man's, and the divorce rate among couples 50 and older has just about doubled since the 1990s. These two forces mean that eight out of 10 women will end up alone and solely responsible for their financial well-being, said Jane Schwartzberg, head of client segments for UBS Wealth Management USA.

"It's a big problem because we're not going to be prepared for what inevitably is going to come," she said.

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Nearly 60% of widows and divorcees said they wish they had been more involved in the financial planning decisions, with 56% of women discovering hidden debt, inadequate savings or overly conservative or aggressive investments that affected their lifestyle and retirement goals.

Nearly all the surveyed widows and divorcees advised younger women to get more involved in their long-term finances now, the report found.

So why aren't women getting the message? It's not as if they aren't touching money at all. In fact, married women are completely comfortable and savvy handling the bulk of the day-to-day finances of the household. But when it comes to planning for retirement or investment, they are either uninterested or believe their husbands are better equipped, the report found.

Gender roles are certainly hard to shake, with men traditionally handling the long-term financial planning decisions instead of their wives. Men also tend to make more money than women, and in this report, 70% of the men were the breadwinners. But of the female breadwinners in the report, 43% said they leave financial decisions to their husbands.

Lack of confidence is also a big factor.

The report found that in heterosexual marriages, both men and women are convinced that men are better equipped to invest, understand financial topics and make long-term financial decisions.

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"The belief that men somehow can do this better and know better is totally unsubstantiated," said Schwartzberg.

Women also need to know that you don't need to be an expert to handle retirement and investment decisions.

To meaningfully engage in your finances, you just need to be able to answer straight forward questions such as who are the people that matter most to you and what do you want to accomplish in life, Schwartzberg said.

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The perpetuation of men controlling investment and money decisions is likely to continue. The report also found that 69% of fathers and 52% of mothers with children under 21 said they were fine with their daughters' future spouses handling long-term financial planning.

"That means to me they don't understand the cost. They don't understand that a critical component of living in an equal way and with equal choices and equal freedoms, equal opportunities is having a seat at the table financially," said Schwartzberg.