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The question

Some women reach menopause much earlier than others, often for reasons unknown. Might weight be a factor in this?

This study

The researchers analyzed data on 78,759 women, all pre-menopausal and most in their mid-30s at the start of the study, which spanned about 22 years. In that time, 2,804 women reached menopause before age 45, which is considered early. All of the women reached menopause naturally, none because of a hysterectomy, oophorectomy, radiation therapy or chemotherapy. Compared with normal-weight women, those who were underweight — with a body mass index (BMI) below 18.5 — were 30 percent more likely to have experienced early menopause. By contrast, early menopause was less likely for overweight women than for those of normal weight: 21 percent less for those with a BMI of 25 to 27.4 and 30 percent for a BMI of 27.5 to 29.9. The chances of early menopause also were greater — by 50 percent — for women who had been underweight at age 18 vs. those whose weight was normal at that age.

Who may be affected?

Women. Menopause marks the end of a woman's menstrual cycle. In the United States, most women reach menopause in their 40s or 50s, most at about age 51. Menopause occurs naturally as the amount of estrogen and progesterone produced by the body declines, eventually causing the ovaries to stop producing eggs and periods to cease. After menopause, a woman cannot become pregnant.

Caveats

Some data came from responses on questionnaires. Most participants were white, so the results may not apply to others.

Find this study

Online Oct. 25 in Human Reproduction (academic.oup.com/humrep; click on "More Content," then "Advance Articles").

Learn more

Information on menopause can be found at womenshealth.­gov/menopause and at ­menopause.­­­­org (search for "menopause 101").

The research described in Quick Study comes from credible, peer-reviewed journals.