Women have more to fear than men when it comes to facing the financial risks of retirement, according to a new report.

Noting that one in five single women age 65 or older is living in poverty, the authors of the report warned that the situation could worse as more baby boomers step out of the work force.

"Women are at a real risk of living a life of poverty in their older years," says Cindy Hounsell, president of the Women's Institute for a Secure Retirement (WISER), which commissioned the report.

Based on surveys and a roundtable discussion with more than 30 retirement experts, the report lists a number of reasons why women are particularly vulnerable going into retirement. Among the findings:

-    Women at age 65 are expected to live, on average, another 20 years-four years longer than men. That means they will need to save more for retirement.
-    Less than half of today's working women have access to pension or retirement savings plans at work.
-    Women are likely to spend some of their retirement years alone due to widowhood or divorce. For women age 85 and older, only 13% are married with a spouse present.
-    Nearly 40% of older women living alone depend on Social Security for almost all of their income, and more than half would be living in poverty were it not for their Social Security benefits.