AssessmentsAmenorrhea: Pathology Review
USMLE® Step 1 style questions USMLE
A 35-year-old woman comes to the office with complaints of irregular menstruation. She has had only two periods in the last year. Menarche was at age 12, and she had a regular menstrual cycle until 12 months ago. The patient also reports feeling flushed at night without provocation and experiencing occasional dyspareunia with post-coital spotting. Past medical history is noncontributory. Temperature is 36.9°C (98.5°F), pulse is 70/min, respirations are 13/min, and blood pressure is 118/76 mmHg. Cardiopulmonary and abdominal exams are unremarkable. The patient has Tanner stage V breasts and pubic hair. Pelvic examination reveals a small anteverted uterus and minimal vaginal rugations. Abdominal examination is within normal limits. Urine pregnancy test is negative. Serum TSH is 3.2 µU/mL. Which of the following set of hormonal changes will most likely be observed in this patient?
Content Reviewers:Antonella Melani, MD
Two people come to the clinic one day. First you see Ana, a 17 year old teenage girl. Ana comes with her mother, who’s worried because Ana hasn’t had her first period yet.
Upon physical examination, you notice that Ana is quite short for her age. In addition, she has a wide neck, broad chest, and poorly developed breasts with widely spaced nipples. You decide to perform a blood test, which reveals low estrogen levels and high FSH and LH.
Next, comes María, a 25 year old female who’s concerned because she hasn’t had her period for nine months now.
She’s sexually active, so the first thing you do is ask for a pregnancy test, which comes up negative.
When asked about physical activities, she refers to going for a 2-hour run every single day, plus swimming and then tennis on weekdays.
Regarding her diet, she’s very strict when it comes to avoiding fatty foods. On physical examination, you realize that María is underweight, and a blood test reveals low levels of estrogen, LH, and FSH.
First, the hypothalamus secretes gonadotropin-releasing hormone, or GnRH for short, which goes to the anterior pituitary to stimulate the release of gonadotropic hormones, which are luteinizing hormone or LH, and follicle-stimulating hormone or FSH.
LH and FSH then stimulate the gonads to produce sex hormones; in females, LH and FSH stimulate the ovaries to secrete estrogen and progesterone, which are responsible for the female primary sexual characteristics.
LH and FSH are also responsible for the development of secondary sex characteristics that aren’t required for reproduction, like breast development, hip widening, and hair growth mainly on the axillae and genital areas.
Now, once sex hormones have done their job, they signal the hypothalamus and pituitary to turn off the secretion of GnRH, FSH, and LH.
Menarche, which refers