Early or premature menopause is one that occurs before a woman is 40, whether it is natural or induced. The symptoms are similar to those of natural menopause - hot flashes, sleep problems, feeling emotionally upset, dryness of the vagina and often a loss of interest in sex. They can range from hardly noticeable to debilitating.

Women in premature menopause have an increased risk of bone breakage due to osteoporosis as their bones get start getting thinner earlier.

Let's look at why premature menopause can happen:

CHROMOSOME DEFECTS:

Women with Turner's syndrome have no second X chromosome or they may be born without a part of it. This means that their ovaries don't develop properly and the result is a premature menopause.

GENETICS:

If a percentage of the women in your family have stopped their monthly periods early in life, it's possible that you may too.

AUTOIMMUNE DISEASES:

In autoimmune diseases, like Hashimoto's Thyroiditis or rheumatoid arthritis, the body's immune system goes haywire. It's there to protect the body and fight off disease but it can mistakenly attack the body instead. If it attacks the reproductive system it may damage the ovaries and affect the correct production of female hormones.

If a woman has surgery to remove both her ovaries (a bilateral oophorectomy) she will immediately go into a menopause. Her periods will stop and hormone production will plummet. She may start to experience menopausal symptoms right away. These women are offered MHT - menopause hormone therapy.

If a woman has an hysterectomy but is left with one or both ovaries, she won't have a premature menopause, as hormone production can continue. As there is no longer a uterus, she will not have any more periods and cannot become pregnant. Rarely, hot flashes may occur but this is due to the blood supply being disturbed during surgery, and not to hormones. These women may have their natural menopause brought forward by a year or two.

Some cancer treatments, including some forms of chemotherapy and radiotherapy to the pelvic area, may damage the ovaries. If damage occurs, the woman's periods may stop, she may have problems with future fertility or become infertile altogether. This can be immediate or may take several months to occur.

The risks of entering early menopause depend on which type of chemotherapy is given, how much of it was used and how old the woman is when she receives the treatment. As a general rule, the younger a women is the less likely she is to go into a premature menopause.

HOW WILL I KNOW IF I'M IN PREMATURE MENOPAUSE?

If you're under the age of 40 and suffering any menopausal symptoms, see your doctor. In suspected early menopause, blood tests will be needed to make a true diagnosis.

You may be given a blood test that measures follicle-stimulating hormone or FSH. This is the hormone that ovaries use to make estrogen, so when levels of FSH rise, it indicates that the ovaries are no longer making it. A higher than normal level of FSH would show that you are in menopause - but as estrogen levels vary from day to day, you may need to have this test repeated more than once for a definite diagnosis.

You may also have blood tests for estradiol (a kind of estrogen) and luetinizing hormone (LH). When the ovaries fail, estradiol levels go down, so a lower than normal level would show that you are in menopause. Luetinizing hormone triggers ovulation and if levels of it are higher than normal, the diagnosis will be that you've gone through menopause.