Menstrual dysfunction can signal an underlying abnormality that may have long-term health consequences. Although frequent or prolonged bleeding usually prompts a woman to seek medical attention, infrequent or absent bleeding may seem less troubling and the patient may not bring it to the attention of the physician. Thus, a focused menstrual history is a critical part of every encounter with a female patient. Pelvic pain is a common complaint that may relate to an abnormality of the reproductive organs but also may be of gastrointestinal, urinary tract, or musculoskeletal origin. Depending on its cause, pelvic pain may require urgent surgical attention. Recent guidelines no longer recommend routine pelvic examination in asymptomatic, average-risk women other than periodic cervical cancer screening. However, pelvic examination is an important part of the evaluation of amenorrhea, abnormal uterine bleeding, and pelvic pain.
DEFINITION AND PREVALENCE
Amenorrhea refers to the absence of menstrual periods. Amenorrhea is classified as primary if menstrual bleeding has never occurred in the absence of hormonal treatment or secondary if menstrual periods cease for 3–6 months. Primary amenorrhea is a rare disorder that occurs in <1% of the female population. However, between 3 and 5% of women experience at least 3 months of secondary amenorrhea in any specific year. There is no evidence that race or ethnicity influences the prevalence of amenorrhea. However, because of the importance of adequate nutrition for normal reproductive function, both the age at menarche and the prevalence of secondary amenorrhea vary significantly in different parts of the world.
Oligomenorrhea is defined as a cycle length >35 days or <10 menses per year. Both the frequency and the amount of vaginal bleeding are irregular in oligomenorrhea, and moliminal symptoms (premenstrual breast tenderness, food cravings, mood lability), suggestive of ovulation, are variably present. Anovulation can also present with intermenstrual intervals <24 days or vaginal bleeding for >7 days. Frequent or heavy irregular bleeding is termed dysfunctional uterine bleeding if anatomic uterine and outflow tract lesions or a bleeding diathesis have been excluded. Oligo- or anovulation are most frequently associated with polycystic ovarian syndrome (PCOS).
The absence of menarche (the first menstrual period) by age 16 has been used traditionally to define primary amenorrhea. However, other factors, such as growth, secondary sexual characteristics, and the presence of cyclic pelvic pain, also influence the age at which primary amenorrhea should be investigated. Recent studies suggest that puberty is occurring at an earlier age, particularly in obese girls. However, it is important to note that these data reflect earlier breast development alone with minimal change in the age of menarche. Thus, an evaluation for amenorrhea should be initiated by age 15 or 16 in the presence of normal growth and secondary sexual characteristics; age 13 in the absence of secondary sexual characteristics or if height is less than the third percentile; age 12 or 13 in the presence of breast development and cyclic pelvic pain; or within 2 years of breast development if menarche, has not occurred.
Secondary Amenorrhea or Oligomenorrhea
Irregular cycles are relatively common for up to 3 years after menarche and for 1–2 years before the final menstrual period. In the intervening years, menstrual cycle length is ~28 days, with an intermenstrual interval normally ranging between 25 and 35 days. Cycle-to-cycle variability in an individual woman who is ovulating consistently is generally +/− 2 days. Pregnancy is the most common cause of amenorrhea and should be excluded early in any evaluation of menstrual ...