Question

A 32-year-old G0 woman presents with irregular menses occurring every six to eight weeks for the past eight months. The bleeding alternates between light and heavy. Her irregular menses were treated successfully with medroxyprogesterone acetate (MPA), 10 mg every day, taken for 10 days each month. By which mechanism does the MPA control her periods

Answer 1

B. Converts endometrium from proliferative to secretory

Step-by-step explanation:

Patients with anovulatory bleeding have predominantly proliferative endometrium from unopposed stimulation by estrogen. Progestins inhibit further endometrial growth, converting the proliferative to secretory endometrium. Withdrawal of the progestin then mimics the effect of the involution of the corpus luteum, creating a normal sloughing of the endometrium. Stimulation of rapid endometrial growth, conversion of proliferative to secretory endometrium, and regeneration of the functional layer describe effects of estrogen on the endometrium. Inhibin is increased in the luteal phase.