Narrator: This is Science Today. The risk of marital strain for couples having babies in the Nineties is higher than it was a decade ago. Phillip Cowan, a professor of psychology at the University of California, Berkeley has studied young families for two decades and says a lot of the difficulty stems from having different expectations.

Cowan: Out there in the media, what tends to happen is there's new families and everybody is doing things equally and doing the household tasks equally and they're bringing up the children. That's not happening in any reality that I know of in this country or any industrialized country in the world.

Narrator: This disillusionment leads to higher stress and divorce rates.

Cowan: We're not just saying that this is a stressful time. The couples that we interviewed and talk with are telling us that it's stressful and the thing that we know in our study is that conflict between husbands and wives goes up after having babies and satisfaction with the marriage, on average, tends to go down. And we can't blame the babies. That's not the problem.

Narrator: For Science Today, I'm Larissa Branin.