Dysfunctional Uterine Bleeding The term dysfunctional uterine bleeding (DUB) is used to describe abnormal bleeding for which no specific cause was found. It is used as a diagnosis rather than a symptom; although there is no agreement about a simpler term to replace the phrase, idiopathic heavy, regular bleeding, idiopathic heavy, irregular bleeding, and idiopathic prolonged, irregular bleeding were suggested (141). DUB is often used as a diagnosis of exclusion, which is probably more confusing than enlightening. Other terms that are commonly used to describe bleeding abnormalities include anovulatory uterine bleeding and abnormal uterine bleeding (143).
Most anovulatory bleeding results from what is termed estrogen breakthrough. In the absence of ovulation and the production of progesterone, the endometrium responds to estrogen stimulation with proliferation. This endometrial growth without periodic shedding results in eventual breakdown of the fragile endometrial tissue. Healing within the endometrium is irregular and dyssynchronous. Relatively low levels of estrogen stimulation will result in irregular and prolonged bleeding, whereas higher sustained levels result in episodes of amenorrhea followed by acute, heavy bleeding.
Pregnancy-Related Bleeding Spontaneous abortion can be associated with excessive or prolonged bleeding. A woman may be unaware that she conceived and may seek care because of abnormal bleeding. In the United States, more than 50% of pregnancies are unintended, and about 7% of women are at risk for unintended pregnancy but use no method of contraception (94,144). These women may be at particular risk for bleeding related to an unsuspected pregnancy. About one-half of unintended pregnancies result from nonuse of contraception; the other
Table 14.10 Abnormal Menses—Terminology
Table 14.11 Menstrual Terminology one-half result from contraceptive failures (145). Unintended pregnancies are most likely to occur among adolescents and women older than 40 years of age (see Chapter 10). If an ectopic pregnancy is ruled out, the management of spontaneous abortion may include either observation, if the bleeding is not excessive; medical or pharmacologic uterine evacuation (with misoprostol); or surgical management with suction curettage or D&C, depending on the clinician’s judgment and the patient’s preference (146–148). Surgical management appears to be the most likely technique to result in complete evacuation; lower rates of success are seen with both medical and expectant management, although the type of miscarriage and gestational age affect these rates (149) (see Chapter 20).
Exogenous Hormones Irregular bleeding that occurs while a woman is using contraceptive hormones should be considered in a different context than bleeding that occurs in the absence of exogenous hormone use. Breakthrough bleeding during the first 1 to 3 months of oral contraceptive use occurs in as many as 30% to 40% of users; it should almost always be managed expectantly with reassurance because the frequency of breakthrough bleeding decreases with each subsequent month of use (66). Irregular bleeding can result from inconsistent use (150–152). Other estrogen-progestin delivery systems, including the contraceptive patch, vaginal ring, and intramuscular regimens, are associated with irregular breakthrough bleeding. These nondaily contraceptive regimens may promote successful use, making irregular bleeding a less important factor for some women in assessing the balance of risks versus benefits (see Chapter 10).