Menstrual Cycle Physiology and Female Infertility - Test 2

Question 1

Describe the physiology of the switch from negative to positive feedback that is responsible for the LH surge in the menstrual cycle.

Answer 1

Once estradiol levels reach a threshold, it acts on a different population of kisspeptin neurons that stimulate GnRH neurons to release GnRH in response to estradiol binding

Question 2

Name the hormones corresponding to the numbers marked on the graph.

Answer 2

Question 3

What hormonal changes are responsible for the onset of menses?

Answer 3

Withdrawal of estradiol and progesterone

Question 4

Which hormone predominates during the follicular phase of the ovarian cycle? What stage of the uterine cycle corresponds to this phase?

Answer 4

Estradiol

Proliferative phase of the uterine cycle

Question 5

Not all women have the same exact length of menstrual cycles. Which phase of the ovarian cycle is the most variable, accounting for this variability?

Answer 5

Preovulatory/follicular phase

Question 6

The LH surge triggers extrusion of the oocyte and signals to the part of the follicle that remained in the ovary to become the ______ ______ (beginning of the luteal phase)

Answer 6

corpus luteum

Question 7

In the luteal phase, the corpus luteum makes ________ to maintain the endometrial lining, E2, and inhibin. If there is fertilization, the syncytiotrophoblasts make _____ and rescue the corpus luteum so that it can keep making _______ (same as 1st blank) until the placenta takes over.

If no fertilization occurs -> no hCG -> corpus luteum regresses after ~10 days after ovulation -> plasma progesterone and E2 drop -> menses

Answer 7

corpus luteum makes progesterone to maintain endometrial lining; must be rescued by hCG to maintain this if fertilization occurs

Question 8

Describe the two-compartment model of sex steroid production in the ovary.

Answer 8

LH stimulates theca cells to make androgens (androstenedione and testosterone).

Granulosa cells have aromatase; the androgens diffuse across the basement membrane from theca cells -> granulosa cells and granulosa cells convert the androgens to E2 (estradiol)

Question 9

A blood test to check a woman’s ovarian reserve involves measuring serum ____ levels.

Answer 9

AMH (anti-Mullerian hormone)

Question 10

Following ovulation, the granulosa cells that are left behind form the corpus luteum. This is when these cells switch from making primarily ________ (a hormone) to ________ (another hormone).

Answer 10

estrogen before ovulation (follicular phase); switch to progesterone after ovulation (luteal phase)

Question 11

Name the drugs that can be used to induce ovulation in women who have an ovulatory disorder. What are their MOAs?

Answer 11

Clomiphine citrate is a partial estrogen agonist-antagonist (activates upon binding but fails to dissociate)

Letrozole is an aromatase inhibitor

Question 12

How to metal ions like copper affect endogenous hormones such that they are effective contraceptive drugs?

Answer 12

They cause dissociation of E2 from their receptors

Question 13

Describe the change in frequency of LH (and GnRH) pulses from the follicular phase to the luteal phase of the ovarian cycle.

Answer 13

Follicular phase - frequency of gonadotropin secretory pulses is high

Luteal phase - frequency of gonadotropin secretory pulses slows down

Question 14

Do you remember Kallmann syndrome?

Answer 14

Ok good

Question 15

Anorexia nervosa, poor nutrition, and exercise-induced amenorrhea are all characterized by amenorrhea due to inhibition of….?

Answer 15

GnRH release

Question 16

What is the female athlete triad?

Answer 16

1. Eating disorders or negative energy balance
2. Menstrual dysfunction
3. Osteoporosis/decreased bone density

Question 17

_______________ (a disease) is characterized by a premature loss of follicles -> decreased circulating AMH, decreased estradiol, and elevated FSH.

How is it treated?

Answer 17

Primary ovarian insufficiency

Treatment: estrogen-progestin replacement therapy

Question 18

Name four presenting signs/symptoms and one common lab finding associated with PCOS. What is required to make the Dx?

Answer 18

Signs of hyperandrogenism (hirsutism and acne)

Obesity is common

Insulin resistant

Acanthosis nigricans (hyperpigmented areas of skin, often in skin folds)

Dyslipidemia

Required for the Dx: oligoovulation/anovulation, excess androgen activity, polycystic appearance of ovaries on ultrasound (need 2 of 3)

Question 19

What is the treatment for PCOS?

Answer 19

• Treatment: oral contraceptives + anti-androgens
  
  • Spironolactone can antagonize testosterone receptors
  • Flutamide competes for androgen receptors
  • Finasteride is a 5-alpha reductase inhibitor

Question 20

What is Mayer-Rokitansky-Kuster-Hauser Syndrome?

Answer 20

2nd most common etiology of primary amenorrhea; type of Mullerian agenesis: mullerian duct doesn’t develop properly -> absent uterus, fallopian tubes, no upper 2/3 of vagina

Question 21

Menstrual pain that is not associated with identifiable pelvic disease is often diagnosed as…?

What is the treatment for it?

Answer 21

Primary dysmenorrhea

Treatment: NSAIDs to inhibit prostaglandin synthesis (ibuprofen), combined oral contraceptives are second line

Question 22

An infertility work-up will often include a ___________ to assess for patency of the oviducts.

Answer 22

Hysterosalpingogram (HSP)

Question 23

What is the differential for a premenopausal women who presents with abnormal vaginal/uterine bleeding?

Answer 23

Pregnancy

Thyroid disease (hyper or hypo)

Hyperprolactinemia

Premature ovarian insufficiency

Cancer

Question 24

What are the ways to determine a woman’s ovulatory status?

Answer 24

Basal body temperature (increases ~1C at the time of ovulation)

Mittelschmerz can be a predictor for some women

Cycle tracking with serum LH measurements