Source: U.S. Department of Health and Human Services, Office on Women's Health

Menopause is the point in time when a woman's menstrual periods stop. Some people call the years leading up to a woman's last period "menopause," but that time actually is perimenopause.

Periods can stop for a while and then start again, so a woman is considered to have been through menopause only after a full year without periods. (There also can't be some other reason for the periods stopping like being sick or pregnant.) After menopause, a woman no longer can get pregnant. It is common to experience symptoms such as hot flashes in the time around menopause.

The average age of menopause is 51, but for some women it happens in their 40s or later in their 50s. Sometimes called "the change of life," menopause is a normal part of life.

Practice Safe Sex

After a year without a period, you cannot get pregnant. But unsafe sex could still put you at risk for sexually transmitted infections (STIs).

What is perimenopause?

Perimenopause (PER-ee-MEN-oh-pawz), which is sometimes called "the menopausal transition," is the time leading up to a woman's last period. During this time, a woman will have changes in her levels of the hormones estrogen (ES-truh-jin) and progesterone (proh-JES-tuh-RONE). These changes may cause symptoms like hot flashes. Some symptoms can last for months or years after a woman's period stops. After menopause, a woman is in postmenopause, which lasts the rest of her life.

When to see a doctor

Do not assume that if you miss a couple of periods the cause is menopause. See your doctor to find out if pregnancy or a health problem could be the cause. Also see your doctor if you have not had a period for a year and then start "spotting."

What symptoms might I have before and after menopause?

The hormone changes that happen around menopause affect every woman differently. Also, symptoms sometimes are not caused by menopause but by other aspects of aging instead.

Some changes that might start in the years around menopause include:

1. Irregular periods. Your periods may come more often or less often; last more days or fewer; be lighter or heavier

2. Hot flashes (or flushes). These can cause:

-- Sudden feelings of heat all over or in the upper part of your body

-- Flushing of your face and neck

-- Red blotches on your chest, back, and arms