Menorrhagia – Causes of Prolonged or Heavy Menstrual Bleeding

Amongst the many types of menstrual disorders that occur, heavy menstrual bleeding is a  common complaint. It is known as menorrhagia. The average menstrual cycle is of 28 days with menstruation may lasting for 2 to 7 days, during which time the average blood loss is estimated to be 25 to 80 millilters (about 0.8 to 2.7 fluid ounces).

What is Menorrhagia?

Prolonged or heavy menstrual bleeding lasting for more than 8 to 10 days and blood loss over 80 mL is known as menorrhagia or hypermenorrhea. In menorrhagia, the menstrual cycle is regular but the duration and flow is increased. Excessive bleeding may result in clots coming out with the menstrual blood. Read more on menstrual blood clots.

Menorrhagia should be differentiated from other similar conditions such as :

  • Metrorrhagia or intermenstrual bleeding is bleeding occurring any time in between periods or abnormal vaginal bleeding.
  • Menometrorrhagia or irregular periods is bleeding occurring at irregular intervals, with variations in the amount and duration. Conditions causing intermenstrual bleeding may ultimately lead to menometrorrhagia.
  • Polymenorrhea is too frequent menstruation, occurring within less than 21 days.

Causes of Menorrhagia

The most common causes of menorrhagia include :

  • Uterine fibroids, especially submucosal fibroids
  • Uterine polyps
  • Uterine cancer
  • Endometrial hyperplasia is the excessive proliferation of the cells of the endometrium. This is a benign condition but may lead to uterine cancer in some cases.
  • Complications of pregnancy such as miscarriage.
  • Adenomyosis is the thickening of the uterus caused by the endometrium (uterine lining) growing into the outer muscular wall of the uterus.
  • Hormonal imbalance, as in women approaching menopause, or polycystic ovarian syndrome (PCOS).
  • Dysfunctional uterine bleeding (DUB) is abnormal uterine bleeding without any definite pathology. There may be heavy and/or irregular bleeding. It occurs more frequently at the extremes of reproductive life (adolescence and women over the age of 40) since the cycles are most often anovulatory (without ovulation) but it may also be associated with ovulatory cycles. When all other causes of abnormal uterine bleeding have been excluded and vaginal examination does not reveal any pathology, a diagnosis of DUB is usually reached.
  • Endometriosis
  • Intrauterine device (IUD) for birth control.
  • Endocrine disorders such as thyroid or pituitary disorders.
  • Medication such as anticoagulants and pain relievers like aspirin. Hormone medication, including oral contraceptives, when not used as directed by the doctor.
  • Bleeding disorders such as von Willebrand’s disease.
  • Pelvic inflammatory disease

Complications of Menorrhagia

  • Anemia due to prolonged loss of blood.
  • Menstrual cramps, especially when menorrhagia is associated with passing blood clots.

Diagnosis of Menorrhagia

The evaluation of any abnormal uterine bleeding, including menorrhagia, may be done by :

  • Clinical history. A thorough history will include the amount and duration of menstrual flow, the last menstrual period, age of menarche, and other associated symptoms. Pregnancy should be excluded.
  • Physical examination, including a pelvic examination, may detect a uterine fibroid, uterine polyp or other conditions.
  • Blood tests to investigate for anemia or other medical conditions such as thyroid abnormalities.
  • Pap test
  • Endometrial biopsy
  • Ultrasound
  • Hysterosalpingography
  • Hysteroscopy
  • Sonohysteroscopy
  • Laparoscopy
  • Dilation and curettage (D&C) is considered the “gold standard” for diagnosis of abnormal uterine bleeding such as menorrhagia.

Treatment of Menorrhagia

Medical treatment is often effective and may be preferred in women wishing to have children.


  • The general principles of management include iron supplements for anemia and the use of NSAIDs such as ibuprofen both for pain relief as well as to reduce blood flow.
  • Hormone treatment includes oral contraceptives such as estrogen and progesterone combined pill or progesterone alone. Use of Mirena, a hormonal IUD which releases levonorgestrel, may help control excessive bleeding.
  • Treatment of underlying medical conditions causing menorrhagia.


  • Dilation and curettage (D&C)
  • Endometrial ablation where the first few millimeter thickness of endometrium is removed by means of various techniques such as laser or heat. Future pregnancies may be hampered following this method of treatment.
  • Endometrial resection is where an electrosurgical wire loop is used to remove the endometrium.
  • Surgical procedures depending upon the cause of menorrhagia such as myomectomy for uterine fibroid or polypectomy for uterine polyp removal.
  • Hysterectomy is a definitive treatment for menorrhagia but may not be favored by women who desire to have children.

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