Forty years ago, on TV’s Marcus Welby, M.D. and in real life, women were nurses and secretaries, never doctors. Even 15 years ago, they represented about a quarter of all doctors in the United States and just a quarter of all doctors in Illinois.

Today women comprise nearly a third of all U.S. physicians (276,417 of 954,224) and one in three Illinois doctors (13,274 of 40,255). They are entering all specialties but are best represented in pediatrics and obstetrics-gynecology.

And the numbers continue to grow. As of the 2009–10 academic year, 41,571 men and 37,499 women were enrolled in U.S. medical schools.

That’s good news for research into women’s health, according to Candace Tingen, the director of research programs for the Institute for Women’s Health Research at Northwestern University’s Feinberg School of Medicine. “We’re our own best advocates,” she says.

It also means women may be more likely to talk to their doctors about potential problems, feeling less shy about revealing issues with their bodies to another woman, Tingen says. That can make a life-or-death difference when it comes to, say, a suspicious lump in a breast. “You’re exposing your breast to your doctor, and that can be uncomfortable,” says Tingen. “That communication is so key.”

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