If they ever get as far as enrolling, women get scared out of C.S. courses by constant references to having to stay fresh. More so than many professions, computer science changes. If I go home for, say, ten years with kids (I plan for it to be much longer, actually, since I’ll be homeschooling), my degree when I come back is pretty much useless. Women who want two kids and a career see the possibilities of getting back in as slim.
Me, I think I can contract and keep my resume fresh enough. And I think my husband will be able to provide for us. But if he gets hit by a bus I’ll be able to keep the house and feed the kids, and women with a homemaking degree... had better hope the husband has a lot of life insurance.