You've come a long way, ladies. And that's part of the problem.

Women have narrowed the gap with men over the past few decades in many areas, including one where they would be better off not catching up. According to a new study, over the past 20 years, the rate of heart attacks in middle-age women has been increasing while it has been declining in middle-age men. Men, however, still have higher rates overall. The findings were published in the medical journal Archives of Internal Medicine.

"Historically, we've not been as good at treating women as we have men," says Dr. Paul Moulinie, chief of cardiology at Huntington Hospital. Moulinie traces a lot of the rise in women's heart problems back 40 years, when their rate of smoking began to skyrocket. Teenage girls back then, nudged to pick up cigarettes by tobacco companies (the Virginia Slims brand tied into the equal-rights movement with its "You've come a long way, baby" slogan), are paying the price today.

Moulinie says societal pressures may have added to the stress on women's hearts. He notes that rates of both obesity and diabetes are increasing in women. He also says in the past, doctors often ignored heart-attack warning signs from women because they weren't the classic symptoms typically described by men. For example, a woman might describe a symptom caused by a heart problem as back discomfort. Men are more likely to describe it as chest discomfort. "We're beginning to recognize women's symptoms," he says.

The National Institutes of Health says it is crucial for women to know the warning signs because they "are less likely than men to believe they're having a heart attack and more likely to delay in seeking emergency treatment." The NIH says the warning signs are:

Pain or discomfort in the center of the chest.

Pain or discomfort in other areas of the upper body, including the arms, back, neck, jaw or stomach.

Other symptoms, such as a shortness of breath, breaking out in a cold sweat, nausea or lightheadedness.

While chest pain is the No. 1 warning sign for both men and women, the NIH says women are somewhat more likely than men to experience some of the other common symptoms.