Normal menstruation begins between the ages of 10 and 17 years. Once ovulatory cycles ensue, women will have regular and predictable bleeding every 24-35 days, lasting 3-7 days with a predictable amount of flow. Most women lose 2-4 tablespoons of blood with each menses (30-40 ml). The majority of blood loss occurs over 1-2 days, and scantier amounts of bleeding will occur during the remainder of the cycle. Some women may have 1-2 days during the course of menstruation, when bleeding stops and then spontaneously resumes. Subjectively, each woman will serve as her own control, experiencing menstruation individually and uniquely. Slight variations in pattern, duration, and amount will be alarming and lead a patient to seek an evaluation.
Abnormal uterine bleeding is a common and significant problem during puberty, adolescence, reproductive, and postmenopausal years. Approximately 10 million women annually suffer from abnormal bleeding; many suffer in silence. Menstrual cycle-related complaints account for almost one third of all visits to gynecologists. Depending on the time during the reproductive life cycle, complaints and presentations among women vary widely. In addition, the causes for bleeding vary with the time during the life cycle. In the adolescent, heavy and prolonged bleeding can be severe enough and lead to an emergency room visit but tend to be for benign reasons. During the reproductive years, pregnancy-related concerns and uterine pathology must be addressed. Among postmenopausal women, the new onset of bleeding will require an urgent visit to the gynecologist to exclude malignancy.
The impact of abnormal uterine bleeding and subsequent treatment can be profound. At one extreme, heavy bleeding can be associated with hypotension (low blood pressure), anemia, and subsequent blood transfusions. At the other, it may be associated with the inability to enjoy work, hobbies, or coitus. Women who experience unpredictable and heavy menses often complain of a poor quality of life, with restrictions of work, travel, or sports. They may feel confined and afraid to leave their homes because of their fear of social embarrassment from soiling through clothing and furniture due to unpredictable and uncontrolled bleeding.
Recently the American College of Obstetrics and Gynecology (ACOG) recommended the more descriptive terminology of anovulatory uterine bleeding (AUB) to refer to bleeding not caused by anatomic, organic, or systemic pathological conditions. The spectrum of menstrual abnormalities associated with AUB is generally related to the hormonal abnormalities in the menstrual cycle. These are associated with the loss of regulatory control of the hypothalamic-pituitary-ovarian axis. Symptomatically, the menstrual changes can include changes in the duration and amount of the blood flow.
Many factors can be associated with bleeding from the genital tract. These include pregnancy-related complications, vaginal, cervical, and uterine disease, cancer, systemic diseases, infection, trauma, drugs, and iatro-genic causes. The most common pregnancy-related complications include: miscarriage, incomplete abortion, implantation bleeding, and ectopic pregnancy. Vaginal bleeding can also be caused by anatomic abnormalities within the reproductive tract. These include vaginal polyps, vaginal infections and lacerations, foreign bodies, vaginal cancer, or cervical bleeding. Causes of cervical bleeding include cervical polyps, ectropion (unhealed sore), eversion, cervical cancer, and infections. Uterine abnormalities can include: endometrial atrophy or polyps, fibroids, adenomyosis, endometrial hyperpla-sia, endometrial cancer, and infections. Rarely does fallopian tube cancer or ovarian cancer present as abnormal vaginal bleeding, but these diagnoses must be considered during evaluation of the patient.
A detailed history and physical examination must be obtained in any woman presenting with abnormal bleeding. Systemic diseases must be excluded by a detailed history. Physical inspection of the vulva, vagina, and cervix must be performed on all patients. Thorough bimanual and rectal examinations are important.
Once a thorough physical examination has been performed, laboratory testing and imaging become imperative adjuncts to the evaluation process. Generally, initial laboratory studies will include a complete blood count with platelets and a thyroid-stimulating hormone test. Other laboratory testing including coagulation studies, liver function tests, and hormonal panels may be selected based on the findings during the history or physical examination.
Several diagnostic techniques are available including endometrial biopsy, transvaginal ultrasound, hys-teroscopy, saline infusion sonography (SIS), and magnetic resonance imaging (MRI). Findings obtained from the history and physical examination will dictate which modalities are chosen. The therapy chosen for patients with abnormal uterine bleeding may include a medical or surgical approach or a combination of both. For women with anovulatory menstrual cycles, many effective medical therapies are available. These include oral contraceptive pills, progestin therapy, hormone-impregnated intrauterine devices, nonsteroidal anti-inflammatory drugs, or GnRH analogues. Sometimes correction of other hormones may be needed when their imbalance is determined to be a contributing cause of the bleeding. The choice of medical therapies will be determined by the desire for future childbearing, lack of contraindications for therapy, cost, compliance issues, and the absence of other organic, anatomic, or systemic disease.
Surgical therapies may utilize minimally invasive therapy with removal of polyps or fibroids via operative hysteroscopy (a procedure done with a small tube placed in the uterus). In cases where no anatomic pathology is found and patients desire preservation of the uterus (but not childbearing), patients may be offered a procedure called an endometrial ablation. Hysterectomy may be the ultimate procedure when other therapies have failed or when women expect 100% relief from abnormal bleeding.
Finally, abnormal uterine bleeding affects many patients and spans the reproductive life cycle. The causes of abnormal vaginal bleeding span the gamut from reproductive tract abnormalities to systemic disease. In some cases, the bleeding can be debilitating, in others it is just a minor nuisance. However, a thorough history, physical examination, and carefully chosen imaging and laboratory tests will quickly delineate the etiology, pointing the way to appropriate medical or surgical therapy.
- Jones, K., & Bourne T. (2001). The feasibility of a “one stop” ultrasound-based clinic for the diagnosis and management of abnormal uterine bleeding. Ultrasound Obstetrics and Gynecology, 17, 517—521.
- Munro, M. G. (2000). Abnormal uterine bleeding in the reproductive years. Part I pathogenesis and clinical investigation. Journal of the American Association of Gynecologic Laparoscopists, 6(4), 393-416.