Approximately 30% of all hysterectomies performed in the United States are to treat heavy menstrual bleeding. Conservative therapy, which is now the trend, also helps to control costs and allow women to keep their uterus intact. For many women, heavy menstrual bleeding is very subjective. By definition menorrhagia is menstruation at regular cyclical intervals but with increased flow and length of the menstrual cycle. It is one of the most common complaints in gynecology. By clinical definition, menorrhagia means total blood loss greater than 80 ml per cycle or menstruation that lasts longer than 7 days. According to the World Health Organization, approximately 18 million women in the 30-55-year-old age group complain that their menstrual bleeding is excessive. Of this group, only 10% experienced blood loss which is great enough to cause anemia or is clinically defined as menorrhagia.
A typical menstrual cycle is 21-35 days in length with bleeding lasting an average of 7 days. Total flow usually ranges between 25-80 ml.
Metrorrhagia is defined as bleeding at irregular intervals. Menometrorrhagia is frequent and increased flow. Polymenorrhea is usually defined as bleeding frequently and usually less than 21 days. Dysfunctional uterine bleeding means abnormal bleeding without any systemic abnormality or obvious structural cause.
Understanding the menstrual cycle is important in recognizing the causes of menorrhagia.
When the hypothalamus releases gonadotropin releasing hormone, the pituitary gland produces follicle stimulating hormone and luteinizing hormone. FSH and LH stimulate the ovaries to produce estrogen and progesterone.
The follicular phase of the menstrual cycle is when estrogen production results in an increase in endometrial thickness. This is also called the proliferative phase.
The secretory phase or luteal phase is when progesterone stimulation results in endometrial maturation.
There are many causes of menorrhagia and they can be divided into different groups: anatomic, endocrinologic, organic and iatrogenic. If an investigation does not come up with the cause of menorrhagia, a woman is diagnosed as having dysfunctional uterine bleeding or DUB.
Most of the time DUB can be secondary to anovulation. As a result of anovulation, the corpus luteum does not form and consequently there is no progesterone production. Since the estrogen is not blocked, the endometrium thickens. The endometrial lining will outgrow its blood supply and start to degenerate. The final result is a disorganized breakdown of the endometrial lining.
If there is more than 80 mL of blood lost on a regular basis, then women are at risk for iron deficiency anemia. This can usually be treated with oral ferrous sulfate to replace low iron reserves. If severe enough, symptoms such as shortness of breath, fatigue and palpitations (irregular heart beat) can occur. If the anemia is severe, it may require transfusion and/or intravenous estrogen therapy.
Miscarriage is the most common cause of irregular bleeding in women of childbearing age. Anovulatory bleeding commonly occurs in younger obese women.
Sexually transmitted disease or even simple vaginitis can cause intermenstrual bleeding.
Polycystic ovarian syndrome presents in obese women in an anovulatory state.
Benign tumours such as fibroids and polyps near the endometrial lining can cause painful heavy bleeding. An IUD may be the source of the problem.
Postmenopausal women with any sign of bleeding should be investigated for uterine cancer.
Certain medications such as progestin therapy can cause a withdrawal bleed after they are stopped.
Wonen on anticoagulants should be warned of possible excessive bleeding.
Thyroid abnormalies such as hypothyroidism may result in cold intolerance, dry skin, weight gain, hair loss in addition to increased blood loss. Hyperthryroidism may also cause increased blood flow.
Excessive bleeding can be related to abnormal blood clotting and be found in patient’s with von Willebrand disease or thrombocytopenia.
Organic illnesses such as kidney failure, resistance to hormones and abnormalities in the hypothalamic/pituitary axis can also result in irregular menses.
Whatever the cause is, consult your physician. After a thorough history and phyical exam, they can order the appropriate blood tests and a pelvic ultrasound to check your uterus and ovaries so that the more common causes of heavy menstrual bleeding can be excluded.