Endo: Repro Axis (Women)

Question 1

FSH induces release of ________ (hormone)

LH induces release of ________ (hormone)

Answer 1

FSH induces release of estradiol

LH induces release of progesterone

Question 2

What is activin? (2)

Answer 2

Activin activates the anterior pituitary

It is only present in women

Question 3

Do women ovulate during pregnancy?

Why/why not?

Answer 3

Women DO NOT ovulate while pregnant b/c

1. Placenta produces very high levels of estrogen and progesterone
2. This inhibits anterior pituitary
3. Less FSH, LH is released
4. This prevents ovulation

Question 4

What causes menopause?

Describe the changes in estrogen, inhibin, progesterone, and LH/FSH during menopause.

Answer 4

• Menopause occurs when there are no more follicles left in the ovaries
• Without follicles, no estrogen and inhibin are produced
• Without corpus luteum, no progesterone is produced
• FSH and LH are still being produced by anterior pituitary, but there is no negative feedback from the other hormones so FSH/LH remains high

Question 5

How is menopause diagnosed?

Answer 5

Menopause is diagnosed by 12 months without a period

Question 6

What is contained in an oral contraceptive pill?

How does this affect the anterior pituitary?

Answer 6

• OCP contains estrogen and progesterone
• This provides negative feedback anterior pituitary, reducing FSH and LH

Question 7

How does OCP prevent pregnancy? (4)

Answer 7

1. Suppress ovulation
2. Increased cervical mucous (sperm can’t penetrate cervix)
3. Thins the uterine lining
4. Progesterone slows motility of oocyte through fallopian tube

Question 8

Compare the progesterone and side effects of early and late generation OCP’s

Answer 8

Early gen: acne, bloating, etc (progesterone more similar to testosterone)

Late gen: venous thrombosis (progesterone more similar to estrogen)

Question 9

Why does estrogen reduce acne?

Answer 9

Estrogen increases sex hormone binding protein, which sequesters testosterone and prevents acne

Question 10

What is the purpose and MOA of clomid?

Answer 10

Use: induce ovulation

​MOA: Clomid prevents estradiol from inhibiting anterior pituitary. Anterior pituitary then makes more FSH, inducing oocyte release

Question 11

In females,

• Hypothalamus releases __________
• Anterior Pituitary releases _________
• Ovary releases _____________

Answer 11

In females,

• Hypothalamus releases GnRH
• Anterior Pituitary releases LH, FSH
• Ovary releases estradiol, inhibin, progesterone

Question 12

During pregnancy, where are the majority of your gonadal hormones being produced?

Answer 12

Placenta!

ovaries are largely suppressed

Question 13

Female menstrual cycle:

• When estrogen builds up, ________________
• This causes a surge in _____
• This induces _______ from the ovary
• The remaining ____________ produces _________
• The ____________ degenerates after ___ days, and the uterine lining is shed

Answer 13

Female menstrual cycle:

• When estrogen builds up, negative feedback switches to positive feedback
• This causes a surge in LH release
• This induces ovulation from the ovary
• The remaining corpus luteum produces progesterone
• The corpus luteum degenerates after 14 days, and the uterine lining is shed

Question 14

Describe the negative feedback of estradiol, progesterone, and inhibin

Answer 14

• Estradiol and progesterone both inhibit anterior pituitary and hypothalamus
• Inhibin only inhibits anterior pituitary