通常育龄期的女性大多数在50岁月经周期消失（即人们所谓的停经）。综合多项研究的结果，如今知道“停经过晚（>55岁）的女性易患乳腺癌、子宫内膜癌等；相反，停经过早（<46岁）的女性则易患骨质疏松、心肌梗死和中风。”已知吸烟、营养不良、缺乏体育锻炼、遗传和心理压力过大等因素均可能导致女性过早停经；相反，服用雌激素等保健药品则可显著延长女性的行经年龄。

Early Menopause May Double Heart Disease Risk, Study Says

Quitting smoking might help prolong menstruation, researchers suggest

WEDNESDAY, Sept. 19 (HealthDay News) -- Women who experience early menopause may face double the risk of heart disease and stroke, according to a new study.

This increased risk is true across different ethnic backgrounds and is independent of traditional heart disease and stroke risk factors, the researchers said.

The study included more than 2,500 women, aged 45 to 84, who were followed for between six and eight years. Twenty-eight percent of the women reported early menopause, which occurs before the age of 46.

Women with early menopause had twice the risk of heart disease and stroke compared to other women. The overall number of women in the study who suffered heart attacks (50) and strokes (37) was small, however, the researchers noted.

When a woman's periods have stopped for a year, she has reached menopause.

The study -- which found an association between early menopause and heart risk, but not a cause-and effect connection -- appears in the October issue of the journal Menopause.

"If physicians know a patient has entered menopause before her 46th birthday, they can be extra vigilant in making recommendations and providing treatments to help prevent heart attacks and stroke," study leader Dhananjay Vaidya, an assistant professor in the division of general internal medicine at the Johns Hopkins University School of Medicine in Baltimore, said in a university news release.

"Our results suggest it is also important to avoid early menopause if at all possible," Vaidya said.

For example, smokers reach menopause an average of two years earlier than nonsmokers, so quitting smoking may delay menopause. Other factors that influence the onset of menopause include heredity, diet and exercise.

The researchers also found that the increased risk of heart disease and stroke associated with early menopause was similar whether early menopause occurred naturally or because of surgical removal of reproductive organs. Vaidya noted that women who have a hysterectomy (uterus removal) often have their ovaries removed, which leads to rapid menopause.

"Perhaps ovary removal can be avoided in more instances" in order to delay menopause and possibly protect patients from heart disease and stroke, Vaidya suggested.

Cardiovascular disease is the leading cause of death for women in the United States, according to the U.S. Centers for Disease Control and Prevention.

SOURCE: Johns Hopkins Medicine, news release, Sept. 18, 2012