According to MayoClinic.com, normal menstruation occurs every 21 to 35 days, and may last anywhere between 3 to 7 days. Some women have menstrual bleeding that is more on the heavy side; others have very light bleeding. However, bleeding that occurs irregularly between menstrual periods is always considered abnormal, and is termed metrorrhagia. Irregular bleeding between menstruation can caused by many abnormalities in the female genital tract and hormonal axis.
Dysfunctional Uterine Bleeding
The Merck Manuals Online Medical Library reports that dysfunctional uterine bleeding is the most common cause of irregular menstrual bleeding during the reproductive years. The gynecologist diagnoses the patient as having dysfunctional uterine bleeding after a thorough clinical examination and a battery of laboratory tests exclude other potential causes of irregular bleeding. Most patients presenting with dysfunctional uterine bleeding do not ovulate because of their underlying hormonal imbalance. Dysfunctional uterine bleeding may be treated with a combination oral contraceptive pill or by the induction of ovulation, depending on whether the patient wants to get pregnant or not.
Pregnancy Complications
The Merck Manuals Online Medical Library suggests that pregnancy should be excluded in every woman in her reproductive years presenting with irregular bleeding. Although it may seem unlikely, some women are unaware that they are pregnant, and their pregnancy presents with a bleeding due to a very early pregnancy complication. Some causes of bleeding in early pregnancy are potentially fatal, and need be recognized and diagnosed as soon as possible. For instance, ectopic pregnancy, or pregnancy outside the uterus, can cause irregular bleeding, and if not recognized immediately, can rupture and cause a life-threatening internal bleeding.
Uterine Polyps
MayoClinic.com lists uterine polyps, or growths of the uterine wall which protrude inside the cavity of the uterus, among the causes of irregular menstruation. Most women with uterine polyps are in their forties, but they can also occur in younger age groups. The cause behind the development of uterine polyps is unknown, but it is established that they are more common in hypertensive, obese patients and patients who have undergone Tamoxifen therapy for breast cancer.
