Menorrhagia is a term that is used to mean heavy regular periods. The average menstrual blood loss was determined in a Swedish population study of 476 women, selected by their birthdate, to be approximately 30-40ml; the upper limit of normal was defined as a loss of greater than 80ml, i.e. above the 95th centile. Losses greater than 60-80 ml were associated with an increased incidence of iron deficiency anaemia ().

Complaints of menorrhagia are common: it has been estimated that 31 per 1000 general practitioner consultations by the population at risk are for excessive menstrual bleeding () and that approximately 20000 hysterectomies are performed for menorrhagia per year in the United Kingdom.

Some causes of menorrhagia are listed in Table Some causes of menorrhagia. Fibroids and adenomyosis are common causes of menorrhagia and other local causes must be considered. Intrauterine contraceptive devices (IUCDs) have been shown to cause an increased amount and duration of bleeding in several studies.

Table Some causes of menorrhagia

Local causes

  • Fibroids
  • Adenomyosis
  • Congenital uterine anomaly (e.g. bicornuate uterus)
  • Intrauterine contraceptive device
  • Endometrial or fibroid polyp
  • Endometrial carcinoma
  • Pelvic inflammatory disease

General causes

  • Idiopathic (dysfunctional uterine bleeding)
  • Anovulatory cycles
  • Hypothyroidism
  • Coagulation disorder (such as thrombocytopenia or von Willebrand’s disease) or occasionally anticoagulant therapy

Although it has been suggested that sterilization is a cause of menorrhagia this has not been confirmed when blood loss has been measured (). Many women take the combined contraceptive pill prior to being sterilized and it is likely that their periods are heavier, but often not abnormally heavy, because they stop the pill, rather than as a direct result of sterilization.

General causes of menorrhagia are less common but excessive bleeding has been described in association with coagulation disorders such as thrombocytopenia, von Willebrand’s disease and deficiency of factors II, V, VII, X and XI ().

Anovulatory cycles

Most women with menorrhagia have hormonally normal ovulatory cycles. Anovulatory cycles are often of abnormal length but they can also be of normal length. They occur particularly at the extremes of reproductive life and also in women with the polycystic ovary syndrome; they may be associated with cystic hyperplasia of the endometrium and particularly heavy bleeding after several weeks of amenorrhoea (metropathia haemorrhagica). The heavy bleeding in anovulatory cycles results from the lack of a previous progestogenic effect on the endometrium; the amount of bleeding can often be effectively reduced by the administration of a progestogen such as norethisterone 5mg o.d., b.d. or t.d.s. or medroxyprogesterone acetate 10 mg o.d. from day 5, 12 or 15 to day 25 of the cycle. A progestogen is the treatment of choice for heavy anovulatory bleeding; it has the added advantage that it protects the endometrium from unopposed oestrogen stimulation.


Women with overt hypothyroidism sometimes present with menorrhagia which resolves with adequate thyroxine replacement therapy. No well-designed study on the relationship between hypothyroidism and menorrhagia has, however, been reported. In a recent uncontrolled unstructured study of women with menorrhagia, it was found that those who had an exaggerated TSH response to thyrotrophin releasing hormone had lower mean thyroxine levels (85 versus 105nmol/l) and higher TSH levels (5.9 versus 2.4mu/l) than those with a normal TSH response to TRH, and that their menorrhagia resolved with thyroxine therapy. Serum thyroxine and TSH levels on treatment were similar to those of the untreated group ().

Dysfunctional uterine bleeding

This term is used to mean different things by different authors but it is commonly used to describe heavy menstrual bleeding for which no cause is found, which is said to be the case in about 50% of women with menorrhagia (). Although no cause is determined from the history and examination, an abnormality such as a submucous fibroid may be revealed at the time of hysterectomy. Menorrhagia cannot be termed dysfunctional or idiopathic without either a hysterosalpingogram or hysteroscopy having been performed.

Menorrhagia: Management

The management of menorrhagia is outlined in site. A superficial history is not a good guide to whether a woman does or does not have menorrhagia. What seems to be heavy bleeding to one person is regarded as normal by another and may well be within normal limits; conversely, some women with true menorrhagia do not consider that their periods are heavy. In the Swedish population study, 40% of women with a blood loss greater than 80 ml did not think that they had heavy periods (). On the other hand, 40% of women complaining of menorrhagia have been found to have a blood loss of less than 80 ml in several studies () and in some the loss was less than 10 ml. Questions about the numbers of tampons and towels used per period are also often unhelpful; Fraser et al. () found no correlation between blood loss and number of pads and tampons used. However, as a general guide, heavy bleeding cannot be controlled with tampons alone, with only one towel at a time or without having to get up at night to change tampons and pads.

The most accurate measurement of blood loss is the alkaline haematin method of Hallberg and Nilsson. Haemoglobin is extracted from all towels and tampons used during a period and is converted with sodium hydroxide to haematin, which is measured with a spectrophotometer; the result is compared with that obtained from a similarly treated peripheral blood sample. It has been shown using this method that more than 90% of blood is lost during the first 3 days of a period in women with a normal blood loss, and in those with menorrhagia ().

It is important in the history to enquire about cycle length and duration of bleeding and to determine whether there are other abnormalities such as intermenstrual bleeding and dysmenorrhoea, and also to enquire about contraception. If necessary a menstrual chart can be kept to determine the cycle pattern and whether intermenstrual bleeding is occurring. A general and vaginal examination should be performed and a cervical smear should be taken if indicated.


The necessity for further investigation will depend on the history, the nature and severity of the symptoms, and on the findings on examination and the age of the patient. Menorrhagia will often, but not always, lead to iron deficiency anaemia and a haemoglobin estimation should be performed. If oral iron is administered a normal haemoglobin level may be maintained. If there is intermenstrual bleeding as well as menorrhagia or if the bleeding is very heavy, or if the patient is more than 35 years of age, diagnostic curettage will usually be indicated, preceded by hysteroscopy if available, if no cause for the menorrhagia is identified.

Menorrhagia: Treatment

If menorrhagia is deemed to be due to a specific remediable cause such as an IUCD, a fibroid polyp or a general disorder, appropriate treatment is given. If menorrhagia is thought to be due to a uterine abnormality such as fibroids, adenomyosis or a uterine anomaly, or if no cause can be found, medical treatment can be tried.

Medical treatment of Menorrhagia

The benefits of medical treatment are that it is often effective, it avoids the need for surgery with its associated morbidity (and even mortality), it is usually more acceptable and it allows procrastination and possibly spontaneous resolution of the problem. Disadvantages include the fact that it often needs to be continued for several years, side-effects are common and it is not always effective.

Non-hormonal medical treatment

Prostaglandin synthetase inhibitors such as mefenamic acid 500 mg t.d.s. from the onset of the bleeding have been found to be effective in several studies, the best results being obtained in women with genuinely heavy losses (). They interfere not only with the synthesis of prostaglandins but also with PGE2 receptor binding (). Side-effects are uncommon; gastrointestinal disturbances can usually be avoided by taking the medication with food. One advantage over most forms of hormone therapy is that prostaglandin synthetase inhibitors can be used in women who are trying to conceive, as they are only taken during menstruation.

The suggestion that there may be abnormal fibrinolytic activity in some women with menorrhagia led to treatment with antifibrinolytic agents such as tranexamic acid which inhibits plasminogen activation. It was shown to be of value by Nilsson and Rybo () but it is not often used because of concern about side-effects of nausea, dizziness, vomiting and diarrhoea and the possible risk of thrombosis. Cases of cerebral thrombosis in association with tranexamic acid therapy have been reported ().

Ethamsylate (Dicynene) is thought to promote haemostasis by decreasing capillary fragility and by modifying prostaglandin synthesis. It was found to be effective in reducing excessive blood loss in nine women, in a small placebo controlled study (). Side-effects include nausea, headache and skin rashes.

Treatment with iron is clearly indicated to prevent iron deficiency, or if iron deficiency occurs.

Hormonal treatment

The combined oral contraceptive pill is very effective in decreasing blood loss and it is the treatment of choice for younger women who require contraception, if there are no contraindications.

Progestogens such as norethisterone may be taken either from day 12 or 15 to day 25 or from day 5 to 25 of the cycle, but they are much less effective in ovulatory than in anovulatory cycles. Side-effects include acne, gastrointestinal disturbances, bloating and weight gain.

Danazol was found to be effective in reducing blood loss when taken continuously in a dose of 200mg/day (). This dose was chosen in order to try to reduce side-effects to a minimum, to minimize the cost and also to preserve menstrual bleeding. In 16 women mean menstrual blood loss was decreased from 183 ml to 38 ml and 26 ml in the second and third treatment cycles respectively. Danazol also reduced the severity of dysmenorrhoea in the majority of patients.

A study was performed to compare the efficacy of danazol 100mg b.d. taken continuously for 60 days and mefenamic acid 500 mg t.d.s. taken for 3-5 days from the beginning of the period in two cycles, in two groups of 20 women. Mean blood loss was decreased from 163 ml to 65 ml and from 160 ml to 127 ml by danazol and mefenamic acid respectively; side-effects occurred significantly more often in the women treated with danazol (). After the study, half the women in the danazol group did not want to continue the medication because of side-effects and half in the mefenamic acid group because of lack of efficacy.

Another disadvantage of danazol, in addition to its side-effects, is that it can cause masculinization of a female fetus if it is taken during pregnancy ().


Oestrogens have been found to be useful in the acute management of heavy uterine bleeding unrelated to a complication of pregnancy. In a double blind randomized study, bleeding stopped in 72% of women given intravenous Premarin and in 38% who received placebo (). Oestrogen may promote haemostasis by increasing prostaglandin synthesis and platelet aggregation and also by encouraging regeneration of the endometrium by stimulating production of growth factors.

LHRH agonists

LHRH agonists can be used as temporary treatment for menorrhagia, as they cause amenorrhoea. They are not usually used for longer than 6 months at the present time because of concerns about the effect of low circulating oestrogen levels on bones and because of the cost. Menorrhagia is likely to recur within 2 months of stopping therapy. They can be given to a woman to allow her time to decide whether surgery is an acceptable form of treatment and to allow her haemoglobin level to rise. They can also usefully be given prior to myomectomy to reduce blood loss at the time of surgery. In women with fibroids, the fibroids revert to their original size soon after treatment is stopped ().

Surgical treatment of Menorrhagia

Dilatation and curettage

Diagnostic curettage may decrease the blood loss for a while and it will be reassuring to the woman if the histology of the curettings does not show evidence of malignancy. In women with very heavy bleeding any beneficial effect does not usually last beyond the first period, which may in fact be heavier than previous periods (). If an endometrial polyp is found it can be removed with polyp forceps but such polyps are not a common cause of menorrhagia. They may be missed if hysteroscopy is not performed at the time of curettage. A fibroid polyp may cause very heavy bleeding and should certainly be dealt with surgically, either vaginally or abdominally ().


If a woman has proven menorrhagia in association with fibroids which are thought to be the cause of the menorrhagia, and wishes to conserve her uterus, myomectomy should be considered. The main disadvantages of this operation are bleeding at the time of surgery, adhesion formation which may lead to infertility, and the likelihood that further fibroids will develop. There is also a slight risk of rupture of the uterus if a pregnancy does occur. The administration of an luteinizing hormone releasing hormone agonist for 3 months prior to surgery will reduce the size of the fibroids and also blood loss at the time of surgery.


This is a major operation and as well as a mortality of approximately 1:1000 it has a

significant morbidity. It should only be undertaken when other options have been fully explored and the woman really wants it to be done in the knowledge of the advantages and disadvantages.

Endometrial ablation and resection

Surgical destruction of the endometrium has the advantage of requiring minimal time in hospital and minimal time off work and of avoiding the morbidity of hysterectomy, but it also has some disadvantages.

Endometrial ablation

Laser photovaporization of the endometrium under direct hysteroscopic vision has been used successfully in the management of women with heavy bleeding (), but it is a time-consuming procedure, often taking between 1 and 2 hours (), and is not without risk. Two deaths due to air embolism during this treatment in young women have recently been reported ().

Following treatment the uterine cavity becomes scarred and misshapen and intrauterine adhesions may form. Some women become amenorrhoeic and others have reduced blood loss. Goldrath has reported a success rate of 95% but others have had less satisfactory results ().

Another technique that has recently been described, but not yet adequately evaluated, is radiofrequency-induced thermal endometrial ablation ().

Endometrial resection

This is another method of endometrial destruction. DeCherney et al. () reported the successful use of this technique in women with intractable uterine haemorrhage unresponsive to medical treatment in whom there was a contraindication to hysterectomy.

Magos et al. () described a pilot study of the use of endometrial resection as an alternative to hysterectomy in 16 women, in one of whom it was not actually carried out because of perforation of the uterus. Resection takes less time (20-35 minutes) than laser vaporization, once experience has been gained with the operation, and it provides a histological specimen. It can be tailored to give complete amenorrhoea or continuing lighter periods; dysmenorrhoea is reduced following the procedure. Hysteroscopic examination 3 months after resection showed that in no case was the uterine cavity completely obliterated but in one hysterectomy specimen the cavity was obstructed in several places. Three of the 15 women were not satisfied with the results of resection and two of these requested hysterectomy.

Thus although endometrial destruction shows some promise, there are some disadvantages. One is that if endometrium persists in loculated areas of the uterine cavity a haematometra may form and if malignancy were to occur in such endometrium the patient would present late. Another potential problem is what might happen if a woman becomes pregnant when she has had a partial procedure; so far no pregnancies have been reported. A major anxiety about the procedure is that of safety, including the danger of air embolism or of fluid overload, depending on which technique is used. Clearly the operation should only be undertaken by experienced personnel working in fully equipped units.


Selections from the book: “Introduction to Clinical Reproductive Endocrinology”. Edited by Gillian C. L. Lachelin, 1991.

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