Female Reproductive Function

Question 1

Follicular phase of the ovarian cycle

Answer 1

• FSH stimulates development of follicles

- Estradiol rises

Question 2

Ovulatory phase of the ovarian cycle

Answer 2

• LH surge causes rupture of graafian follicle
• Oocyte discharge
• Mid cycle

Question 3

Luteal phase of the ovarian cycle

Answer 3

• LH converts the ruptured follicle to a corpus luteum
• High progesterone
• Some estradiol

Question 4

Corpus albicans

Answer 4

• Degenerated corpus luteum if fertilization does not occur

- Low estrogen and progesterone

Question 5

Proliferative phase

Answer 5

• Thickness of endometrium increases from 1-2 mm to 8-10mm
• Dominated by estrogens
• Variable in length (usually around 14 days)

Question 6

Secretory phase

Answer 6

• Dominated by progesterone
• Fixed length of 14 days after ovulation
• Promotes accumulation of glycogen, increased glandular secretions, and increased vascularity

Question 7

Menstrual phase

Answer 7

• Prostaglandin mediated vasoconstriction of spiral arteries and local ischemic injury/inflammation
• Regression of corpus luteum
• 5 days

Question 8

Hormonal regulation of the menstrual cycle

Answer 8

• GnRH stimulates release of LH and FSH by pituitary
• Estrogen synthesized by follicles has negative feedback effects
• In late follicular phase estradiol reaches a high level that initiates positive feedback and a surge in LH and FSH, provoking ovulation.
• Luteal phase characterized by negative feedback. Estrogen, progesterone, and inhibin produced by corpus luteum have negative effect on gonadotropin release

Question 9

FSH effect on granulosa cells

Answer 9

• Gene transcription and synthesis of aromatase, activins, and inhibins
• Granulosa cells also have LH receptors

Question 10

LH effect on ovarian theca cells

Answer 10

• Synthesis of progestins and androgens

- Androgens enter granulosa cells and converted to estrogens

Question 11

Activins and inhibins

Answer 11

-Act only on the anterior pituitary

Question 12

Gonadotropin secretion

Answer 12

• GnRH binds a G protein coupled receptor on gonadotroph membrane
• IP3/DAG signaling pathway
• FSH and LH production and secretion stimulated

Question 13

Estrogens

Answer 13

• Inhibit osteoclasts

- Promote fat deposition, and stromal and ductile breast growth

Question 14

Progesterone

Answer 14

-Development of lobules and alveoli in breasts

Question 15

Stimulation of puberty

Answer 15

-Pulsatile secretion of GnRH first at night and then during the day

Question 16

Menopause

Answer 16

• Reduced estrogen production leads to increased gonadotropin production
• Loss of negative feedback from estrogens and progesterones
• FSH changes most drastically, LH also increased

Question 17

Postmenopausal source of estrogen

Answer 17

• Estrone produced by muscle and adipose tissue

- Not as potent as estradiol