Big Firm work, almost by definition, is stressful and unpredictable. The hours alone are enough to dissuade a family-oriented person, particularly a female, from taking more prestigious and rewarding positions in law. Unless one is willing to let her children be raised by hired help, or she is one of the lucky few with a stay-at-home husband, a woman must choose between her career and her family. I worked for a firm that is notorious for its poor retention of women. They tried to appear encouraging and accommodating of their female staff, but they refused to adjust the family-hostile work schedule that was the cause of their problem.
Long, unpredictable hours make life hard, especially for parents. This problem is particularly evident in couples where both parties are attorneys or in otherwise high stress professions. After a while, the question must be asked: "If we are going to have a child, which one of us will stay home?"