Abnormal Uterine Bleeding

Diagnosis

Initially, abnormal vaginal bleeding is assumed to emanate from the uterus. A pelvic examination, including the insertion of a vaginal speculum, is essential to eliminate the possibility that the vulva, vagina, exocervix (or ectocervix), or even the rectum or bladder is actually the source of the bleeding. Early pregnancy and its complications should always be ruled out as the cause of AUB in women of reproductive age.

The newer terminology for menstrual bleeding provides information about four dimensions of a woman's cycle: (1) frequency, (2) regularity, (3) duration, and (4) blood loss. Table 26-1 outlines the normal and abnormal values for each of these dimensions and provides the newer terms to describe the abnormalities. As an example, the assessment of abnormal bleeding in a woman with complaints of “irregular menstruation” can be categorized as follows: If her cycle length (first day of menses to the first day of the next menses) is 23 days, she bleeds for 10 days during each cycle, and she loses 100 mL of blood, this would be described as “frequent, prolonged, and heavy menses.” Other important traditional terms include amenorrhea, which refers to the absence of any menstrual bleeding or spotting for at least 3 months; intermenstrual bleeding, which refers to bleeding between normally spaced menses; and postcoital bleeding, which refers to bleeding after vaginal intercourse.

This newer, more descriptive terminology for patterns of AUB replaces the older, less precise terms listed in Box 26-1 . However, it is important to become familiar with these older terms, because they have been used for decades in clinical practice and in the medical literature and are still used for diagnostic coding purposes.

The newer classification system, called PALM-COEIN, is depicted in Figure 26-1 . Appropriate testing is needed to differentiate the various causes of AUB. The classification system takes into account that there are two different influences on AUB. On the one hand, a woman may have structural abnormalities of her uterus that are the likely causes of her bleeding, with the PALM elements standing for p olyps, a denomyosis, l eiomyomas (fibroids), and m alignancies. Rare problems such as imperforate hymen or transverse vaginal septum are more likely to present with primary amenorrhea and not with chronic bleeding problems. The COEIN portion of the classification system refers to important functional disorders such as c oagulation defects, o varian dysfunction (formerly DUB), e ndometrial (uterine cavity lining) causes, and i atrogenic. A “ n ot yet classified” category completes the acronym and is available for a cause of bleeding that is not currently included or idiopathic.

Chapter 33 covers the causes of infrequent menses (oligomenorrhea) and both primary and secondary amenorrhea. Chapters 35 and 41 address perimenopausal and postmenopausal bleeding. This chapter is focused on the etiology, differential diagnosis, evaluation, and treatments for both acute and chronic heavy menstrual bleeding.

Heavy menstrual bleeding occurs in 9-14% of healthy women of reproductive age and is the reason for up to 20% of outpatient clinic visits by women. Heavy menstrual bleeding can cause severe anemia, but less significant blood loss can diminish a woman's quality of life and even her income when workplace activity is adversely affected.

Acute Excessive Bleeding in Nonpregnant Women of Reproductive Age

The etiologies, workups, and therapies of excessive bleeding can differ for acute heavy bleeding compared with chronic heavy bleeding, although often there is considerable overlap. A woman who presents with heavy bleeding needs to be assessed for hemodynamic stability, anemia, and always the possibility of pregnancy. She should be asked about symptoms of dizziness, shortness of breath, or loss of consciousness. Her vital signs must be assessed for hemodynamic stability. It is helpful to get a description of her current bleeding episode as well as her recent and usual bleeding patterns, along with any previous evaluations or treatments. A complete history, including medication history, can provide insight into which of the PALM-COIEN categories is more likely, but a broad differential should be developed. It is quite possible for a woman to have more than one problem as the cause of her abnormal bleeding. Obvious causes requiring immediate surgeries should be ruled out, such as vaginal trauma or bleeding lacerations, as well as aborting fibroids (leiomyomata).

Hospitalization and transfusion are generally recommended for women who have severe anemia (hemoglobin ≤7 g/dL) and those who are hemodynamically unstable. Outpatient transfusion is an option for women with borderline presentations. Patients who decline blood transfusions or blood products in spite of severe anemia should be cared for by a team experienced with other treatment options. Before a transfusion is started, blood tests should be performed. Box 26-2 lists the tests that should be considered for the workup of AUB.

Baseline hemoglobin is mandatory, and a complete blood count (with red blood cell indices) is performed to determine the chronicity of the problem, to rule out thrombocytopenia, and to identify possible hematologic malignancies. Coagulation factors should be obtained, as well as serum iron, iron-binding capacity, and serum ferritin levels. Following these initial assessments, liver, renal, and thyroid function tests may help to identify other systemic causes of excessive uterine bleeding.

Many of the test results may not be available for days, but the heavy bleeding needs to be promptly controlled. First-line therapy is generally medical. Surgical approaches are usually reserved for women whose condition does not respond to medical therapies and for those who are bleeding so heavily that there is insufficient time to consider medical treatments. First-line medical therapy usually involves hormonal manipulations ( Box 26-3 ).