Menopause occurs when you stop having menstrual periods for twelve months. It is the culmination of the transitional perimenopause phase when your body's reproductive system slows down. By menopause, the ovaries stop producing estrogen, which leads to myriad symptoms including hot flashes (sometimes followed by intense cold, shivering, and sweating), night sweats, sleep problems, urinary problems, vaginal dryness, osteoporosis, joint and muscle pain, back pain, skin changes (less elasticity, thinning, and wrinkling), breast atrophy, forgetfulness, irritability, fatigue, and a loss of sexual interest.

On average, women experience the onset of menopause at fifty-one, but it varies depending on the woman. However, it generally happens between forty and fifty-eight. About 1 percent of women will experience premature menopause, which is defined as menopause that occurs before age forty, and each year, about 263,000 enter surgical menopause after having their ovaries removed.

Menopause can be devastating for some women, not only because of the associated physical symptoms, but because it marks the end of their fertility, which they experience as a loss of womanhood. On a biological level, the estrogen loss associated with menopause may increase a woman's risk of depression. A Dutch study published in the journal Mauritas, found increased rates of depression as women began to experience perimenopause, and as they transitioned from perimenopause to menopause.

Physical Changes

In addition to the typical symptoms brought on by hormonal changes, menopausal women experience a number of physical changes: the skin is less elastic, thinner, and prone to wrinkling; the metabolism slows down, which causes weight gain (especially around the waist); become more forgetful; at higher risk for osteoporosis, which makes bones brittle and prone to breakage, and may even cause “shrinking” in height and affect posture; and a higher risk of heart disease.

Researchers have found that a drop in estrogen and progesterone can increase appetite. Investigators at Oregon Health and Science University, Portland, studied the hunger levels of monkeys that had their ovaries removed and found that in the absence of ovarian hormones, the monkeys increased their food intake by 67 percent and gained 5 percent body weight in a matter of weeks.

Menopause Tests

Just as for perimenopause, the best way to tell if you're in menopause is to gauge your own symptoms. However, if you're concerned that you may be entering menopause prematurely and want to you ask your doctor for tests, here is what you can expect.

Tests for premature menopause may include an FSH blood level measurement, which measures the level of follicle-stimulating hormone and is used to test fertility. The test is usually taken on day three of the menstrual cycle if you are menstruating. Other tests may include testosterone, progesterone (usually done on day twenty-one to check for ovulation), luteinizing hormone, and DHEA levels (which are checked for polycystic ovarian syndrome and/or annovulatory bleeding), and thyroid tests. In 2004, researchers even proposed that ultrasound may let doctors predict how many fertile years a woman has left by measuring the size of her ovaries! However, this test, described in the July 2004 edition of the journal Human Reproduction, has not yet been tested on women.

Saliva testing is often recommended by alternative medicine practitioners as a way to determine if a woman has the right balance of hormones, or if she is experiencing hormonal deficiencies. However, conventional medical experts don't consider saliva testing a proven, reliable, or accurate test, since there's no pre-established “right” level of hormones for postmenopausal women, and hormone levels may not even be related to a woman's physical comfort.

What's Normal; What's Elevated?

Follicle-stimulating hormone levels fluctuate during a woman's menstrual cycle, but normal levels range from 5mIU/mL (milli-international units per millimeter) to 30 mIU/mL for menstruating women, to 50mIU/mL to 100 mIU/mL in menopausal women. In other words, women in menopause have FSH levels up to ten times higher. But the FSH levels can vary greatly for reasons other than menopause, including if a woman is taking hormone therapy or if she has a genetic abnormality called Turner's syndrome or anorexia nervosa; other lesser-supported causes include having ovarian or adrenal cancer, starting puberty very early, or having problems with her hormone-regulating system.