Perimenopause is the period leading up to actual menopause (when 12 months goes by and
you haven’t had a period). Most women go through menopause between ages 45 and 55. On
average, 51 is the age at which American women have their last menstrual period. When
perimenopause starts and how long it lasts varies. Perimenopause can start as early as age 35
and last a few months or a several years.
During perimenopause, the levels of your reproductive hormones estrogen and progesterone
rise and fall unevenly. Your menstrual cycles gradually lengthen, and you begin having
menstrual cycles in which no ovulation takes place. Only during cycles with ovulation is there a
possibility for pregnancy to occur3.
As ovulation becomes more erratic and your body produces less progesterone, you may have
longer and heavier periods. Other physical changes and symptoms common during
perimenopause are due to reduced estrogen production.
Menopause, sometimes called "the change of life," marks the end of your reproductive years.
When you have gone 12 months without a period, menopause is considered complete. Changes
in bleeding are normal as you near menopause; however, any bleeding—even spot bleeding—
that you experience after menopause is not considered normal and could be a sign of a health
problem. That’s why it is important to report any abnormal post—menopausal bleeding to your
The Menstrual Cycle A Time for Change
A Time for Change
During perimenopause, it is natural for periods to become more irregular and, therefore, less
predicable. “Spotting” is also common as menopause grows near. Whereas in years past your
period may have come like clockwork, you may find yourself much more uncertain about when
your period will arrive, how heavy or regular the blood flow will be—and where you will be when
that protection is needed.
2. Midlife Transitions: A guide to approaching menopause. October 2003. The American College of
Obstetricians and Gynecologists.
3."Menopause and Menopause Treatments" August, 2004. Office on Women’s Health. U.S. Department
of Health and Human Services.