I have definitely noticed that married men, especially with children, get preferential treatment with respect to not being expected to work extra outside of normal hours. I don't think it hurts their promotion prospects the way an unmarried man's refusing such extra work would.

That said, I have seen raised eyebrows when child care responsibilities impact men's work within normal working hours.

I have not noticed that women are treated differently than men in these respects, but I probably don't have enough of a sample to draw real conclusions.