Overview of Abnormally Heavy or Prolonged Menstrual Bleeding

Menorrhagia, also called hypermenorrhea, is a menstrual disorder characterized by abnormally heavy and/or prolonged menstruation. The menstrual cycle is a recurrent series of changes that occurs in the female reproductive tract (e.g., uterus, ovaries, cervix) between the onset of puberty and menopause. These changes prepare the sexually mature female body for pregnancy each month and are associated with menstruation, which is the discharge of bloody fluid from the uterus through the vagina.

Menstrual problems are relatively common and about 25 percent of women experience menorrhagia at some point during their reproductive years. Menorrhagia can occur anytime after menstruation begins and before menopause.

Menstrual cycles vary considerably from woman to woman, and in some cases, from month to month in the same woman. The average cycle is 28 days, measured from the beginning of menstruation, but may last 18–40 days. The average menstrual period lasts 4–5 days, but can vary from 3 to 7 days in length. In women with menorrhagia, menstrual periods may occur more often than normal (e.g., every 2 or 3 weeks and/or may last 7–10 days or even longer. In severe cases, women can have their period for 3 weeks out of every month.

During menstruation, the average blood loss is about 40–80 milliliters. Women with menorrhagia may experience heavy bleeding that soaks through one or more sanitary pads or tampons every hour for several hours.

Menstruation is the most common cause for iron deficiency and anemia (low red blood cell count) in women. Blood loss in women with menorrhagia can be much higher than normal, significantly increasing this risk. Symptoms of anemia include the following:

  • Abnormal heart rate (e.g., rapid heart rate [tachycardia], heart palpitations [fluttering])
  • Chest pain (angina)
  • Difficulty breathing
  • Drowsiness
  • Fever
  • Headache
  • Malaise (generally feeling unwell)
  • Pale skin
  • Weakness

Abnormally heavy and/or prolonged menstrual periods also can interfere with normal activities and can have a negative effect on a woman's health and her quality of life.

Menorrhagia can be classified as mild, moderate, or severe, depending on blood hemoglobin levels. Hemoglobin (Hb) is a protein in red blood cells that carries oxygen; levels are measured as grams per deciliter (g/dL). In mild menorrhagia, hemoglobin levels are greater than 12 g/dL; moderate menorrhagia results in a hemoglobin level between 9–12 g/dL; and severe menorrhagia causes a hemoglobin level of less than 9 g/dL.

Publication Review By: the Editorial Staff at HealthCommunities.com

Published: 05 Jan 2011

Last Modified: 28 Jan 2015