February is the American Heart Association's Go Red For Women campaign, to raise awareness that heart disease is the number one killer of women.

Annually, more than 500,000 women die from heart disease.

And Framingham Heart Study researchers have determined that women, who begin puberty before their teens could be at a higher risk of heart disease later in life.

Girls who start menstruating before age 12 are 23 percent more likely to develop heart disease as adults, according to Framingham Heart Study researchers.

Those same girls were said to be at a nearly 30 percent higher risk of death from heart attack or stroke.

Experts currently believe that women may not experience heart problems until nearly a decade on average after men because of the female hormone estrogen, which shields the heart until menopause, around ages 50 to 60, after which its levels drop dramatically, reported Time magazine.

That’s why the Framingham researchers focused on 1,638 female children and third generation participants of the original study members, all over age 40, to see if reproductive factors could be correlated to body weight, and in turn, heart disease risk, reported Time magazine.

Researchers with the Framingham Heart Study recorded factors such as the age at which a woman began menstruating, the number of children she had, and her age at menopause and connected them to obesity-related measures such as fat distribution in the body and types of fat (visceral fat in the belly area versus less metabolically active subcutaneous fat found underneath the skin).

“Understanding whether body fat distribution is associated with female reproductive factors may provide insight into the potential mechanisms linking them to [heart disease] and its risk factors,” the authors write.

And just this week, a new study shows women’s heart disease awareness is increasing, with the number of women aware that heart disease is the leading cause of death nearly doubling in the last 15 years, according to the American Heart Association, which had its office in Framingham on Speen Street, until it moved to Waltham in December.