by the placenta. This hormone (HCG) is necessary for the maintenance of
the endometrium during the first trimester of pregnancy.
At menopause, beginning on an average at age 51, ovarian production of
estrogen and progesterone gradually declines. The resulting release of feed-
back inhibition on the pituitary leads to its greatly increased release of
FSH and LH. The adrenal glands continue to produce a minor amount of
estrogen. Ovulation stops, and menstruation becomes less frequent and even-
tually ceases. The postmenopausal ovary and the adrenal gland continue to
secrete androgens. The conversion of these androgens to estrogens mainly in
fat cells and skin via the enzyme aromatase provides most of circulating estro-
gen in postmenopausal women.
C O M P R E H E N SIO N Q U E ST IO N S
[48.1] An obese 57-year-old woman did not yet exhibit symptoms of
menopause but was diagnosed with polycystic ovary syndrome
(PCOS) and insulin resistance. Her plasma levels of testosterone were
above normal. Which one of the following is most likely in this case?
A. Hyperinsulinemia leading to androgen overproduction by the ovary
and its conversion to estrogen in fat cells
B. Androgen overproduction by the adrenal gland and its conversion
to estrogen in fat cells
C. Progesterone overproduction by the polycystic ovary leading to its
conversion to estrogen
D. LH/FSH ratio = 1
E. Estrogen overproduction by the ovary and conversion to testosterone
[48.2] Which one of the following changes is most likely to be observed in a
postmenopausal woman who is not taking hormone supplementation?
A. Cessation of androgen secretion
B. Increased levels of FSH and LH
C. Increased osteoblast activity
D. Decreased levels of gonadotropin-releasing hormone
E. Increased progesterone levels
[48.3] In a normal premenopausal woman, which one of the following is
stimulated by progesterone?
A. Release of gonadotropin-releasing hormone by the pituitary
C. Development of the endometrium in preparation for possible
D. Uterine contraction
E. Follicle development