The American College of Obstetricians and Gynecologists recently endorsed a new classification of abnormal uterine bleeding that also describes a systematic strategy for its evaluation. This applies to causes of bleeding in women who are not pregnant. It was developed by the International Federation of Gynecology and Obstetrics (FIGO) and has been supported by ACOG so that there were will be an internationally accepted system to evaluate, study and promote treatment of this common problem.

The normal menstrual flow is generally 5 days long and occurs in a cycle that comes between 21 and 35 days apart. Excessive blood loss, or menorrhagia, is usually based on the patient’s perception of what appears to be heavy bleeding to her. The new PALM-COEIN system classifies heavy uterine bleeding, using two major categories: structural or nonstructural.

The most common structural causes include problems within the uterus such as polyps, adenomyosis, fibroids (leiomyomas), pre-cancer and cancer. Polyps are small fragile growths within the uterus or cervix that bleed more easily than normal tissue. Adenomyosis is a condition where the two layers of the uterus, the inner layer (endometrium) and the outer layer (myometrium) are intermingled. Fibroids, otherwise know as leiomyomas, are benign tumors of the uterus found in approximately 30% of women. They can cause pain, bleeding, and infertility.They are usually estrogen dependent benign tumors that slowly grow until the age of menopause. Pre-cancer is known as endometrial hyperplasia, and over time goes through four stages of gradually worsening abnormal tissue, resulting in carcinoma. While not considered in this classification, a major structural cause of abnormal bleeding can be due to complications of pregnancy.

The non-structural causes of bleeding include coagulopathy (bleeding disorder), ovarian dysfunction, endometrial causes, iatrogenic and not yet classified. Coagulopathy refers to a problem primarily with bleeding itself such as von Willebrand Disease or hemophilia, inherited bleeding disorders that are caused by deficient clotting factors. Ovarian dysfunction includes a range of disorders that frequently include polycystic ovary syndrome (PCOS). This bleeding problem results from a hormone imbalance with too much estrogen and not enough progesterone and is commonly due to not having regular ovulations. Iatrogenic causes include medications and herbal remedies that are known to increase bleeding such as Coumadin, Heparin, Motrin, Nuprin, Advil, ibuprofen, aspirin, oral contraceptives, ginkgo, ginseng and motherwort.

Evaluation of abnormal bleeding consists of getting a thorough medical history, physical exam and then laboratory testing. Findings on physical exam that are important include extra hair growth and acne, which can be seen with PCO syndrome, and signs of a bleeding disorder such as frequent bruising and small skin hemorrhages. Laboratory evaluation includes blood tests, imaging studies and tissue sampling. A complete blood count will include a measurement of the platelets, which are important in clot formation, and other bleeding tests are available as needed. Imaging studies generally involve transvaginal ultrasound. Ultrasound is the key tool in evaluating the size and shape of the uterus to look for physical causes of bleeding such as fibroids. It also can reveal thickened endometrial tissue, which can be a sign of endometrial hyperplasia, a pre-cancer. It is a simple, safe, and less expensive tool than magnetic resonance imaging (MRI). Routine use of MRI is not recommended in the evaluation of abnormal uterine bleeding.

Endometrial tissue sampling is recommended in patients with abnormal bleeding to determine whether carcinoma or premalignant lesions are present. If the patient is 45 or older it is the primary test. It should be also done in younger patients when unopposed estrogen is present, when there is obesity or polycystic ovary syndrome, and when the bleeding does not respond to treatment or is persistent. Endometrial sampling can be performed in the office using aspiration, or as an ambulatory procedure with anesthesia so that a more thorough sample can be obtained by dilation and curettage with a visualization of the interior of the uterus, a procedure known as hysteroscopy. Hysteroscopy allows direct visualization of the interior of the uterus and is highly accurate for detecting uterine cancer. A recent review of its accuracy showed that it had an accuracy of 97% and abnormalities were found about 50% of the time.

Adenomyosis is a condition that causes similar symptoms as do fibroids: bleeding and pain with an enlarged uterus. Adenomyosis is due to a mixing up of the lining of the uterus and that of the surrounding uterine muscle, and is more difficult to detect. There may be ultrasound signs of it including an asymmetric appearance to the uterine muscle. Some experts recommend transvaginal ultrasound as the initial screening tool followed by MRI as a second-line test.

In a patient without increased risk of pre-cancer or malignancy, especially in younger patients, sometimes a trial of therapy can be started before proceeding with evaluation. For those with increased risk such as patients with a genetic predisposition to cancer, those over 45 or those with anovulatory cycles associated with unopposed estrogen, treatment should not be started until a complete evaluation has been performed.

Many patients with abnormal heavy bleeding can be successfully treated with medical therapy with progesterone containing medications such as birth control pills, the birth control ring, progesterone given by injection, or progesterone containing IUDs. For those with anatomic causes of bleeding such as polyps or fibroids, surgery is the usual treatment. This may be as simple as a minor procedure such as endometrial ablation (Novasure) or sometimes may involve major surgery such as vaginal or laparoscopic hysterectomy. Pre-cancer usually is curable by medical or surgical treatment. Uterine cancer requires surgery and is usually successful, though additional treatment such as chemotherapy or radiation may be needed. Whenever cancer is present, the earlier the cancer is detected, the easier and faster the person will be cured of their disease.

Abnormal uterine bleeding is caused by many different anatomical and non-structural causes. We are learning more about them every day. Many of these causes can be completely cured. Some may be benign, and some with identical symptoms may be malignant. If you suspect you may have one of these problems, please tell us about it as soon as you realize that it is a change from what is normal for you. In doing so an appropriate evaluation can be completed and the best therapy can be chosen as quickly as possible.