What causes the menopause?

The menopause (or "change of life") is caused by the ovaries stopping working.

A woman is born with a certain number of egg cells in her ovaries and from the time she is still in her mothers womb these cells begin to reduce in number until in her mid fifties usually, these are all gone. 

When this happens the ovaries stop working and she can no longer make the hormone oestrogen. At the same time other hormones made by the brain increase to try and get the ovaries to keep on working. These hormones made by the brain are called gonadotrophins.

Some women have an early menopause, before the age of 45. This can be caused by surgical removal of the ovaries, or some kinds of chemotherapy or radiation treatment. It may also occur after a hysterectomy, when on average the menopause is four years early. Sometimes it occurs for no apparent reason.

What are the symptoms of the menopause?

• Periods become irregular. Initially the time between periods becomes shorter but eventually lengthens before stopping altogether. 
  A gap of more than 6 months between periods is abnormal and needs checking by the doctor
• Hot flushes and sweats (in 40% of women)
• Vaginal dryness and discomfort during sex
• Mood changes, for example, forgetfulness, difficulty concentrating, anxiety and depression may occur

What are the long term effects of the menopause?

1. Increased risk of heart disease. After the menopause women are three times more likely to develop coronary artery disease
2. Osteoporosis (thinning of the bones) which can make women more likely to break bones.
3. Alzheimer's Disease is probably more common in women who have less of the female hormone Oestrogen. This is the hormone that is no longer made after the menopause. 

What are the advantages of hormone replacement therapy (HRT)?

• Feeling better, women often notice that they have a greater feeling of well being 
• Hot flushes stop, but can return when the HRT is stopped
• Vaginal dryness and discomfort during sex is improved
• Osteoporosis is postponed until the HRT is stopped
• The risk of bowel cancer may be reduced in those on the combined form of HRT (oestrogen plus progestogen)

What are the disadvantages of HRT?

• Increased risk of deep vein thrombosis, and pulmonary embolism (potentially fatal). However this is still a fairly small risk in women on HRT. After surgery or if immobilised for a long time, women should consider stopping HRT.
• Breast cancer is more common, the risk is greater the longer HRT is taken, possibly after only a few years.
• Increased risk of endometrial cancer (cancer of the lining of the womb). This risk is reduced by using the hormone progestogen in combination with oestrogen. However, after 10 years of use, 2 out of 100 women will have developed endometrial cancer because of using HRT.
• There may be a small increase in the risk of heart attacks and strokes for those taking the combined form of HRT (oestrogen and progestogen). It is not yet known if the "oestrogen only" form of HRT has this effect.

How can I decide if HRT is right for me?

It all depends on what is important to you, for example, are you prepared to take some fairly small risks for the sake of feeling better in yourself, or do you prefer to minimize all risk whatever the costs. 

A family or personal history of osteoporosis can make the long term advantages worth the risk of taking HRT.

A family history of breast cancer or thrombosis may make you think twice about HRT.

A good compromise may be to take HRT for a year or two, as current evidence is that the risks of breast and endometrial cancer appear to increase more rapidly after this period.

The best thing is to come and discuss your own situation with one of the doctors.

When can I stop using contraception?

Come and discuss this with us, but as a general rule, women under the age of 50 should wait until 2 years after the last period, and those over 50 should wait one year after their last period.

Matters are more complicated of course if you are taking HRT or are on the oral contraceptive pill, as you won't know if you have been through the menopause.

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On this page

• What are the symptoms of the menopause?
• What are the long term effects of the menopause?
• What are the advantages of hormone replacement therapy (HRT)?
• What are the disadvantages of HRT?
• How can I decide if HRT is right for me?
• When can I stop using contraception?

See also

• National Osteoporosis Society Helpline 01761 472721
  (Mon to Fri 9.30 am - 5pm)
  www.nos.org.uk
• The Amarant Trust for more information about the menopause. Phone Mon-Fri, 11am-6pm on 
  01293 413000.