Menorrhagia is an abnormally heavy and prolonged menstrual period at regular intervals. Causes may be due to abnormal blood clotting, disruption of normal hormonal regulation of periods or disorders of the endometrial lining of the uterus. Depending upon the cause, it may be associated with abnormally painful periods (dysmenorrhea).
A normal menstrual cycle is 21-35 days in duration, with bleeding lasting an average of 5 days and total blood flow between 25 and 80 mL. A blood loss of greater than 80 ml or lasting longer than 7 days constitutes menorrhagia (also called hypermenorrhea). Some authors use menorrhagia exclusively when describing excessive quantity and hypermenorrhea for prolonged duration (although most use both terms interchangeably in the clinical setting). In practice this is not usually directly measured by patients or doctors. Menorrhagia also occurs at predictable and normal (usually about 28 days) intervals, distinguishing it from menometrorrhagia, which occurs at irregular and more frequent intervals. It is possible to estimate the amount of bleeding by the number of tampons or pads a woman uses during her period. As a guide a regular tampon fully soaked will hold about 5ml of blood. One may also have lighter cycles in volume, but blood flow may continue more than seven days thus constituting menorrhagia. An OB/GYN should still be consulted.
Aside from the social distress of dealing with a prolonged and heavy period, over time the blood loss may prove to be greater than the body iron reserves or the rate of blood replenishment, leading to anemia. Symptoms attributable to the anemia may include shortness of breath, tiredness, weakness, tingling and numbness in fingers and toes, headaches, depression, becoming cold more easily, and poor concentration.
Usually no causative abnormality can be identified and treatment is directed at the symptom, rather than a specific mechanism. A brief overview of causes is given below, followed by a more formal medical list based on the nature of the menstrual cycle experienced.
Disorders of coagulation
With the shedding of an endometrial lining`s blood vessels, normal coagulation process must occur to limit and eventually stop the blood flow. Blood disorders of platelets (such as ITP) or coagulation (such as von Willebrand disease) or use of anticoagulant medication (such as warfarin) are therefore possible causes, although a rare minority of cases. Platelet function studies pfa col/epi can also be used to ascertain platelet function abnormalities
Excessive build up in endometrial lining
Periods soon after the onset of menstruation in girls (the menarche) and just before menopause may in some women be particularly heavy. Hormonal disorders involving the ovaries-pituitary-hypothalamus (the `ovarian endocrine axis`) account for many cases, and hormonal-based treatments may regulate effectively. The lining of the uterus builds up naturally under the hormonal effects of pregnancy, and an early spontaneous miscarriage may be mistaken for a heavier than normal period. As women age and move towards menopause, ovulation is delayed and the remaining follicles in the ovaries become resistant to FSH (the follicle-stimulating hormone) secreted by the hypothalamus gland in the brain. Either that or they don`t develop an egg, and thus no progesterone is produced. Without progesterone, the estrogen is unopposed and keeps building up the lining of the uterus. During a woman`s period, the menstrual fluid which is normally shed never gets the signal to stop thickening. It keeps growing and sheds irregularly. Due to the extra thickness, the bleeding is unusually heavy. Less frequently in this age group, too little estrogen causes the irregular bleeding. Most cases of hemorrhagic are due to normal hormonal changes preceding menopause. Irritation of the endometrium may result in increased blood flow, e.g. from infection (acute or chronic pelvic inflammatory disease) or the contraceptive intrauterine device (note the distinction from the IntraUterine System which is used to treat this condition). Fibroids in the wall of the womb sometimes can cause increase menstrual loss if they protrude into the central cavity and so thereby increase endometrium`s surface area. Abnormalities of the endometrium such as adenomyosis (so called internal endometriosis ) where there is extension into the wall of the womb gives rise to enlarged tender uterus. Note, true endometriosis is a cause of pain (dysmenorrhoea) but usually not alteration in menstrual blood loss. Endometrial carcinoma (cancer of the uterine lining) usually causes irregular bleeding, rather than the cyclical pattern of menorrhagia. Bleeding in between periods (intermenstrual bleeding or IMB) or after the menopause (post-menopausal bleeding or PMB) should always be considered suspicious.
- Excessive menses but normal cycle:
- Fibroids ( leiomyoma )
- Ovarian endocrine disorder (dysfunctional uterine bleeding or DUB)(the most common cause)
- Coagulation defects (rare)
- endometrial carcinoma
- endometrial polyp
- Pelvic inflammatory disease
- Short cycle (<21 days) but normal menses (epimenorrhoea or polymenorrhoea). These are always anovulatory cycles due to hormonal disorders.
- Short cycle and excessive menses (epimenorrhagia) due to ovarian dysfunction and may be secondary to blockage of blood vessels by tumours.
- Excessive menses and long intervals.
- Anovular ovarian disorder due to prolonged oestrogen production.
- This may occur following prolonged continuous courses of the combined oral contraceptive pill (e.g. where several packets are taken without a withdrawal gap in order to defer menstruation).
- Risk Factors
- Estrogen administration (without progestogens)
- Prior treatment with progestational agents or oral contraceptives increases the risk of endometrial atrophy, but decreases the risk of endometrial hyperplasia or neoplasia
- Pelvic and rectal examination
- Pap smear
- Pelvic ultrasound scan is the first line diagnostic tool for identifying structural abnormalities.
- Endometrial biopsy to exclude endometrial cancer or atypical hyperplasia
- Differential Diagnosis
- Pregnancy complications:
- Ectopic pregnancy
- Incomplete abortion
- Threatened abortion
- Nonuterine bleeding:
- Cervical ectropion/erosion
- Cervical neoplasia/polyp
- Cervical or vaginal trauma
- Atrophic vaginitis
- Foreign bodies
- Pelvic inflammatory disease (PID):
Where an underlying cause can be identified, treatment may be directed at this. Clearly heavy periods at the start and end of a women`s reproductive years may settle spontaneously (the menopause being the cessation of periods). If the degree of bleeding is mild, all that may be sought by the woman is the reassurance that there is no sinister underlying cause. If anaemia occurs then iron tablets may be used to help restore normal hemoglobin levels. Treatment may be given for a fixed period of time to replenish the body stores. Alternatively therapy may be continued long-term, often in a cyclical regimen on the days of menstruation. The condition is often be treated with hormones, particularly as dysfunctional uterine bleeding commonly occurs in the early and late menstrual years when contraception is also sought. Usually oral combined contraceptive or progesterone only pills may be taken for a few months, but for longer-term treatment the alternatives of injected Depo Provera or the more recent progesterone releasing IntraUterine System may be used. Fibroids may respond to hormonal treatment, else require surgical removal. Anti-inflammatory medication has previously been used, although it has a greater effect on dysmenorrhoea excess pain than on the heaviness of the period (typically 30% reduction in flow). More effective is the use of tranexamic acid tablets that may reduce loss by up to 50%. This may be combined with hormonal medication previously mentioned. A definitive treatment for menorrhagia is to perform hysterectomy (removal of the uterus). The risks of the procedure have been reduced with measures to reduce the risk of deep vein thrombosis after surgery, and the switch from the front abdominal to vaginal approach greatly minimizing the discomfort and recuperation time for the patient; however extensive fibroids may make the womb too large for removal by the vaginal approach. Small fibroids may be dealt with by local removal (myomectomy). A further surgical technique is endometrial ablation (destruction) by the use of applied heat (thermoablation). A non-surgical approach has been the introduction and use of the IntraUterine System.
NOTE: Management of bleeding in pregnancy requires gynaecology referral and potential hospital admission especially if bleeding does not stop or is substantial and surgical intervention is required. Blood transfusions may be required for blood loss resulting in compromised hemodynamic stability. Treatment options include pharmaceutical or surgical and radiological options: Pharmaceutical treatments These have been ranked by the UK`s National Institute for Health and Clinical Excellence:
- First line
- IntraUterine System insertion
- Second Line
- Tranexamic acid an antifibrinolytic agent
- Non-steroidal anti-inflammatory drugs (NSAIDs)
- Combined oral contraceptive pills to prevent proliferation of the endometrium
- Third line
- Oral progestogen (e.g. norethisterone), to prevent proliferation of the endometrium
- Injected progestogen (e.g. Depo provera)
- Other options
- Gonadotrophin-releasing hormone (GnRH) agonists (e.g. Goserelin)
Surgical and radiological treatments
- Dilation and curettage (D&C) is no longer performed for cases of simple menorrhagia, having a reserved role if a spontaneous abortion is incomplete
- Endometrial ablation
- Uterine artery embolisation (UAE)
- Hysteroscopic myomectomy to remove fibroids over 3 cm in diameter