Fights over finances are a commonly known cause of stress and divorce, and a new survey indicates that while the average couple fights over money five times a year, they discuss finances reasonably fewer than two times a month. Every couple knows there are some topics you just don't bring up - his mother's dreadful cooking, your uncle's bad manners. Money, however, should never be among those subjects you don't discuss - especially if you're planning your wedding.

"In today's economy, it's rare that a couple enters matrimony debt-free," notes Carrie Braxdale, managing director of investor services for TD Ameritrade, Inc. ("TD Ameritrade"), a broker-dealer subsidiary of TD Ameritrade Holding Corporation. "Yet many newly engaged couples may be as hesitant - or even more so - to discuss finances as couples who have been together for years. They can get a jump-start on a lifetime of wedded bliss, however, if they take time to talk frankly about finances before they walk down the aisle."

The survey conducted by TD Ameritrade Holding Corporation and LearnVest, found that couples today face three top concerns when it comes to their finances: Not having enough money to retire (27 percent), not having enough money to live as they wish (25 percent), and not having enough money to even live comfortably (24 percent).

Trust over money also emerged as a big issue. Forty percent of respondents do not completely trust their partner to manage their combined finances. Just over one in five (21 percent) admit they sometimes hide their spending from their partner. Thirty-eight percent say they are either unaware or only partially aware of their mate's debts. Perhaps they feel that ignorance is bliss.

Braxdale offers some advice to couples looking to take control of their finances and learn to talk effectively about money:

* Be open about debt before you say "I do." Keeping secrets about how much you each owe on student loans, credit cards or auto loans is no way to start off a marriage. While talking about money might not be the most romantic conversation you ever have with your intended, it's one of the most important.

* Check your credit scores. You'll both keep your own score after you're married, but purchases you make as a couple afterward - like a house or car - can be affected by both your scores. Check your scores at least once a year; doing so can help you catch and correct errors or fraud, and help you better manage your credit and overall finances.

* More people are marrying later in life, so one or both partners may enter the union with a 401(k), IRA or other investment accounts. It's important to discuss long-term retirement savings goals, and understand how you both plan to manage these accounts. Websites like TD Ameritrade's Life 2.0 and Retirement Planning can help by offering access to free resources like retirement calculators and portfolio planners. You'll also find information on making financial decisions that can help you meet your financial goals, whether you're just starting out in your life together, growing your family or approaching your retirement years.

* Get to know each other's saving and spending habits. One partner may be frugal and the other more of a spender, but arguments don't have to be inevitable. You'll need to discuss your habits and work together to find spending and saving solutions that work best for both of you, and for your shared financial goals.

* Build a budget that incorporates savings goals, income and expenses. Discuss whether combined or separate bank accounts make the most sense for you, and be sure your financial goals are in sync.

"Open discussions about money, credit, retirement savings and financial health are an important step toward a healthy relationship," Braxdale says.