TO MAKE YOUR MARRIAGE LAST, DON'T FIGHT ABOUT IT PART 2:

There is, however, one problem with all these studies, as most of the researchers readily admit. It's a different world today than it was years ago when many of these projects began. The gender roles are less clearly defined, the breadwinner is not always the male anymore, and women are free to venture where no female would have gone even a couple of decades ago.

But interestingly, researchers at Ohio State University in Columbus found that one thing that is not likely to change over the decades is the level of conflict between the partners. These researchers followed nearly 1,000 couples over 20 years, beginning in 1980, and found surprisingly little change in the amount of conflict over that length of time.

That study, based on data collected during the Life Course survey at Penn State University, found a slight decrease in the amount of conflict in the final years of the project, but it was very small.

The researchers also found that couples who reported little conflict in their marriage were more likely to share decision making with their spouse, another critical factor in maintaining a healthy relationship. The researchers concluded that if both spouses think they have a say in decision making, they are more satisfied with the marriage and less likely to fight.

That research also touched briefly on an issue that is rarely discussed in this type of research. Partners who believed marriage is forever reported lower levels of conflict than those who weren't all that sure it was going to last. That suggests that attitude and expectations, particularly when entering the relationship, are extremely important.

"People who believe marriage should last forever may also believe fighting is just not worth it," psychologist Claire Kamp Dush said in releasing the study. "They may be more likely to just let disagreements go."

Incidentally, while the Berkeley researchers found that a conflict is ended most easily when the wife cools down, research from Penn State suggests that it's possible to cool down too much. The wife needs to stay engaged or the husband may ignore her ideas and run over her.

The answer, the Penn State team reported in 2003, may be testosterone.

Yup, the bad boy among sex hormones isn't necessarily all bad. In the first study to measure the level of testosterone, infamous for promoting aggression and assertiveness, in both the husband and wife, the researchers found that women with a higher level than average for women were more likely to take an active and supporting role in the marriage, even in resolving conflicts.

That was especially true when the wife had higher testosterone and the husband had lower than average for men.