The root of the problem for women is that their income tends to be lower while they're working so the amount they can save for retirement tends to be less. In fact, women face a triple whammy when it comes to accumulating the money to put aside.

First off, women earn about 20% less than men. Second, women are more likely to spend years out of the workforce raising kids or taking care of ill parents or in-laws. Finally, women are more likely to have part-time jobs. These unfair facts of life end up escalating into some serious money shortfalls in retirement.

To start with, the smaller and fewer paychecks women tend to have during their working years mean lower Social Security benefits during retirement. The Social Security problem is amplified for women who are unmarried: It's the only source of retirement income for 25% of unmarried women. And between vesting rules, time away from a job and lower earnings, it shouldn't come as any surprise that fewer women receive retirement plan payouts and when they do their benefits are lower.

The widow factor

Women who survive their spouses may face yet another triple whammy. A husband's death means one less Social Security check coming in. And, if retirement plan benefits were coming in from a husband's plan in the form of a one-life annuity (just for his life), that's the end of another monthly check. The economic shock can be tremendous. The third leg of this whammy--the many women who allow their husbands to handle all the finances are now on their own and they are more likely to be unfamiliar with financial matters.

At best, this can lead to poor investment choices. At worst, this can lead to the loss of the entire retirement nest egg either through manipulation by unscrupulous individuals or just a lack of understanding as to the risks and costs of certain types of investments.

What women can do to ensure a comfortable retirement

Now, here's some good news. Women live longer than men do, statistically 6-7 years longer. But that means that women either need to accumulate a bigger nest egg, or set up a smarter retirement plan with their spouse to make sure that they both will be guaranteed a secure retirement. Here are some steps you can take to make sure your retirement is everything you hope:

If you are single

If you are single, the best thing you can do is start saving as early as possible. Statistically, women do make less than men, but by saving early the power of compound growth can help ease up the savings gap. As a single woman, you have the sole responsibility for becoming financially literate. So, start cracking the books and financial magazines and surfing the financial Web sites to become a savvy investor and saver.

If you are married