I work in a field called Physical Medicine and Rehabilitation (PM&R), which means that I'm pretty much constantly explaining what I do...
"I'm a PGY4 in PM&R."
"You're a what in what?"
Basically, we deal with sports and other musculoskeletal injuries, as well as the subacute medical management of patients with neurological injuries, including brain and spinal cord injury. It's supposedly a "lifestyle" specialty, which is illustrated by the joke that PM&R stands for Plenty of Money and Relaxation.
Of course, it's not all money and relaxation, especially during residency. But considering I had no in-house call, even during my first year after internship, I can't complain too much.
Lifestyle specialties are usually popular among all applying med students, not just women who want to have kids. That or skin is just SUPER interesting. It's definitely a lot easier to have children if you're in a specialty where the hours are manageable. I won't lie and say that lifestyle wasn't a significant part of my decision.
PM&R is somewhat like psychiatry in that it's a lifestyle specialty that isn't terribly competitive, probably because people don't want to do what we do or don't know about it. The more competitive lifestyle specialties are dermatology and radiology. Family medicine is another favorite among women who want to have kids (it's got "family" in the name, so it MUST be family-friendly). There are some internal medicine specialties that seem to attract more women, like rheumatology and endocrinology; cardiology, not so much.
Anesthesiology was extremely popular among women in my med school class. I never quite understood that, because the hours in residency seemed pretty rough, and it's one of those residencies that tends to get harder as you progress, with more responsibility. But apparently, the jobs after residency are great.
As everyone knows, the field that is probably most dominated by women is OB/GYN, which is decidedly NOT a lifestyle specialty. But I guess you have to do what you love, even if it doesn't necessarily have hours you love.