Porth's Essentials of Pathophysiology, 4e

1039

Disorders of the Female Genitourinary System

C h a p t e r 4 0

tumors; anorexia nervosa; or strenuous physical exer- cise, which can alter the critical body fat–to–muscle ratio needed for menses to occur. 46 Diagnostic evaluation resembles that for dysfunc- tional uterine bleeding, with the possible addition of a computed tomographic scan or MRI to exclude a pituitary tumor. Treatment is based on correcting the underlying cause and inducing menstruation with cyclic progesterone or combined estrogen–progesterone regimens. Dysmenorrhea Dysmenorrhea is pain or discomfort with menstrua- tion. Although not usually a serious medical prob- lem, it causes some degree of monthly disability for a significant number of women. There are two forms of dysmenorrhea: primary and secondary. Primary dysmenorrhea is caused by the effects of excess prostaglandin production in the endometrium. 47 Prostaglandins are potent smooth muscle stimulants that cause intense uterine contractions. Prostaglandin production in the uterus normally increases under the influence of progesterone, reaching a peak at or soon after the onset of menstruation. With onset of men- struation, formed prostaglandins are released from the shedding endometrium. Prostaglandins also cause contraction of smooth muscle elsewhere in the body. Severe dysmenorrhea may be associated with systemic symptoms such as headache, nausea, vomiting, and diarrhea. The pain of primary dysmenorrhea is often diffusely located in the lower abdomen or suprapubic area, radiating to the lower back. The pain is often described as cramping and spasmodic, or similar to labor pains. Secondary dysmenorrhea is menstrual pain caused by structural abnormalities or disease processes such as endometriosis, uterine fibroids, ade- nomyosis, pelvic adhesions, IUDs, or PID. In women with secondary dysmenorrhea, the pain often lasts longer than the menstrual period; it may begin before menstrual bleeding begins; and it may become worse during menstruation. Treatment for primary dysmenorrhea is directed at symptom control. 47 Women with primary dysmenor- rhea generally experience dramatic pain relief with the nonsteroidal anti-inflammatory drugs (e.g., ibuprofen, naproxen, mefenamic acid), which are prostaglandin synthetase inhibitors. Ovulation suppression and symp- tomatic relief of dysmenorrhea can be instituted simulta- neously with the use of hormonal contraceptives. Relief of secondary dysmenorrhea depends on identifying the cause of the problem. Medical or surgical intervention may be needed to eliminate the problem. Premenstrual Syndrome Disorders Premenstrual syndrome disorders are a group of physi- cal, emotional, and behavioral changes that occur in a regular, cyclic relationship to the luteal phase of the menstrual cycle and that interfere with some aspect of

simultaneously degenerate, or the needs of an enlarged endometrial tissue mass may exceed the capabilities of the functioning follicles. Estrogen and progesterone deficiencies are associated with the absence of ovula- tion, hence the term anovulatory bleeding . Because the vasoconstriction and myometrial contractions that nor- mally accompany menstruation are caused by proges- terone, anovulatory bleeding seldom is accompanied by cramps, and the flow frequently is heavy. Anovulatory cycles are common among adolescents during the first several years after menarche, when ovarian function is becoming established, and among perimenopausal women, whose ovarian function is beginning to decline. Dysfunctional bleeding can originate as a primary disorder of the ovaries or uterus or as a secondary defect in ovarian function related to hypothalamic- pituitary stimulation. The latter can be initiated by emotional stress, marked variation in weight (i.e., sud- den gain or loss), or nonspecific endocrine or metabolic disturbances. Nonhormonal causes of irregular men- strual bleeding include endometrial polyps, submuco- sal myoma (i.e., fibroid), bleeding disorder (e.g., von Willebrand disease, platelet dysfunction), endometrial dysplasia, and cancer. The treatment of dysfunctional bleeding depends on what is identified as the probable cause. The mini- mum evaluation should include a detailed history with emphasis on bleeding pattern and a physical examina- tion. A pregnancy test is important to rule out any com- plications of pregnancy. Endocrine studies (e.g., FSH/ LH ratio, prolactin, androgen levels), ultrasonography of the endometrium, and endometrial biopsy may be needed for diagnosis. Nonhormonal causes generally require surgical intervention. Dilatation of cervix and scraping of the endometrium (D&C) can be therapeutic as well as diagnostic. Endometrial ablation (destruction of the basal layer of the endometrium from which the monthly buildup generates) has become a primary treat- ment method for abnormal uterine bleeding. 11 Various ablation devices are available; some use heat while oth- ers use cryotherapy. If nonhormonal problems have been excluded and alterations in hormone levels are the primary cause, treatment may include the use of oral contraceptives, cyclic progesterone therapy, or long-acting progesterone injections or implants. Amenorrhea There are two types of amenorrhea: primary and sec- ondary. Primary amenorrhea is the failure to menstru- ate by 15 years of age, or by 13 years of age if failure to menstruate is accompanied by absence of second- ary sex characteristics. 46 Secondary amenorrhea is the cessation of menses for at least 6 months in a woman who has established normal menstrual cycles. Primary amenorrhea usually is caused by gonadal dysgenesis, congenital müllerian agenesis, testicular feminization, or a hypothalamic-pituitary-ovarian axis disorder. Causes of secondary amenorrhea include ovarian, pitu- itary, or hypothalamic dysfunction; intrauterine adhe- sions; infections (e.g., tuberculosis, syphilis); pituitary