Menopause is a retrospective diagnosis 12 months after menstrual periods have stopped. The average age of the menopause is 50 years and nine months, and is often two or three years earlier in smokers.
About one in five women have had a hysterectomy, or use a levonorgestrel IUD, in which case they cease menstruating anyway. Sometimes women who have undergone hysterectomy with ovarian conservation have a premature menopause before the age of 45 years and may be completely asymptomatic.
A premature menopause is under the age of 45 years. It can be familial, genetic (Turner syndrome), autoimmune, idiopathic; or after surgery, chemotherapy or radiotherapy. A woman with a premature menopause should be referred to a specialist gynaecology clinic.
Often women in their twenties with a premature menopause need much higher doses than conventional HRT. They also need psychological support. These women will benefit from HRT up to the age of 50 years.
The perimenopause is the two or three years before a woman's periods finally cease. Usually, the woman's periods get closer together (every two to three weeks), then change to a five- to six-week cycle, then miss cycles and eventually stop altogether.
Women may consult in the perimenopause if they are anaemic due to menorrhagia (check Hb), find their erratic periods difficult, or are concerned about hot flushes, palpitations, emotional lability and poor memory.
Irregular bleeding should be investigated and referred. A bimanual examination may suggest fibroids, which can be investigated by ultrasound. A speculum exam will see any cervical erosions or polyps. A smear test may be appropriate.
It is unnecessary to measure FSH or LH levels in women over 45 as every woman over this age is perimenopausal to some extent and levels can fluctuate significantly. You cannot 'predict' when periods will stop.
The only use for FSH levels is as part of the investigation into premature menopause in an amenorrhoeic woman under 45 years (two FSH tests more than 30 IU/L, six weeks apart), or in a young woman after hysterectomy with ovarian conservation who is feeling unwell.
More than 80 per cent of women do not want HRT, but do seek a consultation with a primary healthcare professional for information and advice. This is a good time to offer a woman health promotional advice such as diet and breast awareness.
The MHRA (then the Committee on Safety of Medicines) issued advice1 based on data from the Women's Health Initiative (WHI)2 and Million Women Study.3 It stated that HRT may be used for severe menopausal symptom relief if the woman fully understands the treatment, and HRT is prescribed in the lowest possible dosage for the shortest possible time. It also stated that the HRT may no longer be considered as first-line treatment for osteoporosis, because the long-term breast cancer risk is deemed too great.
If a woman has an intact uterus and requires short-term HRT, this should be both estrogen and progestogen, even if she has had a transcervical resection of the endometrium. This can be in any formulation, including tablets, patches and gels.
It is usually progestogen that causes side-effects, including bloating, breast tenderness, acne, premenstrual syndrome, nausea and low mood. If so, change the formulation or consider the levonorgestrel IUD device.
After hysterectomy, patients only require estrogen replacement. However, for those who have had pelvic clearance for endometriosis, some specialists argue continuous combined HRT should be given to suppress any endometriotic tissue.
Many women seem to have the view that combined HRT is dangerous, however many do not appreciate that lifestyle changes could reduce cancer risk.
The Million Women Study3 shows that breast cancer risk doubles in women with a BMI over 30, women who drink three or more units of alcohol a day, or take combined HRT.
The breast cancer risk for women requiring estrogen alone is more controversial. The 'estrogen-only' arm of the WHI trial was stopped after seven years with no increased risk. The Million Women Study also showed that the risk of breast cancer increased by 1.3-fold for estrogen-only compared with twofold for combined HRT.
Previous breast cancer is a contraindication to HRT.
HRT increases thromboembolic risk by 213 per cent, but, to put this in context, for 10,000 years use of HRT, there would be two extra cases of thromboembolic disease. Previous thromboembolic disease is a contraindication to any HRT including selective estrogen-regulator modulators.
Women deciding to end HRT should be weaned off slowly over six months. Halve the dosage for two to three months, then halve again for three months before stopping. Women may wish to start a herbal remedy such as red clover tablets while taking the lowest dosage of HRT.
Many women will ask about alternative therapies. Only red clover has an evidence base to show it reduces menopausal hot flushes, anxiety and depression. A recent article summarised the lack of evidence of most alternative therapies.4
There is an excellent website, Menopause Matters5 that provides helpful information for both patients and health professionals. Healthcare professionals may also find the Map of Medicine menopause pathway particularly helpful (see diagram).6
- Dr Hope is a GP in Woodstock, Oxfordshire and an honorary research fellow in women's health at the University of Oxford
1. Committee on Safety of Medicines. Further advice on safety of HRT: risk-benefit unfavourable for first-line use in prevention of osteoporosis. 2003. CSM CEM/CMO/2003/19.
2. The Women's Health Initiative steering committee. Effects of conjugated equine estrogen in postmenopausal women with hysterectomy: the Women's Health Initiative randomized controlled trial. JAMA 2004; 291: 1701-12.
3. Beral V; Million Women Study Collaborators. Breast cancer and hormone replacement therapy in the Million Women Study. Lancet 2003; 362: 419-27.
4. Herbal medicines for menopausal symptoms. Drug Ther Bull 2009; 47(1): 2-6.
5. Menopause Matters. www.menopausematters.co.uk
6. NHS Evidence. Map of Medicine menopause pathway. Available from: http://nhsevidence.mapofmedicine.com/evidence/map/menopause1.html (accessed 27 August 2010).