A 50-year-old woman comes to the office concerned that her menstrual periods have stopped. She took oral contraceptive pills for the past 17 years, which she discontinued 3 months ago, and her menses have not returned. The patient had one spontaneous abortion at age 27 and otherwise has never been pregnant. She is monogamous with her husband, and they have sexual intercourse regularly. The patient has some vaginal dryness but no pain or discomfort with intercourse. BMI is 21 kg/m2 and vital signs are normal. Speculum examination shows a normal vaginal mucosa and cervix. Bimanual examination shows a normal uterus and ovaries. Urine pregnancy test is negative. Which of the following hormones is most likely elevated in this patient?
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Menopause is defined by the permanent cessation of menses for 12 months and is a normal event of aging caused by exhaustion of ovarian follicles. The mean age of menopause in the United States is 51. Ovarian failure before age 35 is considered premature. During the menopausal transition, FSH levels increase due to resistant ovarian follicles and lack of feedback from inhibin. Absence of menstrual cycles with associated hypoestrogenic symptoms (eg, hot flashes, vaginal dryness) is highly suggestive of menopause. Menopause is typically diagnosed clinically. However, if the diagnosis is unclear, an elevated serum FSH level can be used for diagnosis as it is a reliable early indicator.
Cyclic and continuous oral contraceptive (OC) regimens are not associated with irregular menses or amenorrhea, and premenopausal patients who stop taking OCs should expect spontaneous return of menses. This patient's age and vaginal dryness make menopausal transition the most likely cause of amenorrhea. OCs may mask vasomotor symptoms that are typical of menopausal transition, and the patient was likely having iatrogenic withdrawal bleeding.
(Choice A) A urine pregnancy test should be performed for any female of reproductive age with amenorrhea. A negative test is a reliable indicator that the patient is not pregnant. Serum β-hCG testing is indicated in cases when the absolute value of the β-hCG would aid in diagnosis and treatment, such as in ectopic or molar pregnancies.
(Choices B and D) Estradiol and progesterone levels gradually decrease during the menopausal transition due to decreasing ovarian function. Serum estradiol measurement is not a reliable indicator of menopause due to typical fluctuations and gradual decline. After menopause, estrone is produced outside the ovaries and replaces estradiol as the predominant circulating estrogen.
(Choice E) Serum prolactin levels are much less significantly changed during menopause than are FSH levels. Amenorrhea due to a prolactinoma would be diagnosed by detecting an elevated prolactin level. Additional symptoms can include galactorrhea and headache, which this patient does not have.
Educational objective:
Menopause occurs on average at age 51 and is diagnosable retrospectively after 12 months of amenorrhea. An elevated serum FSH level confirms the diagnosis.