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Flashcards in Normal Menstrual Cycle Deck (105)
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1
Q

What is the average duration of the menstrual cycle?

A

28 days +/- 7 days

2
Q

What are the three phases of the menstrual cycle?

A
  1. Follicular phase
  2. Ovulation
  3. Luteal phase
3
Q

What is the duration of the follicular phase? (physiologically speaking)

A

Onset of menses to the LH surge

4
Q

What is the duration of the ovulation phase? (physiologically speaking)

A

Occurs within 30-36 hours of LH surge

5
Q

What is the duration of the luteal phase? (physiologically speaking)

A

Begins on the day of the LH surge, and ends with menses

6
Q

How long (in days) do the follicular and luteal phases last?

A

14 days

7
Q

True or false: with irregular menses, the duration of the luteal phase can vary, but the follicular phase stays constant

A

False–other way around–follicular phase varies, while the luteal phase remains constant

8
Q

What happens to a woman’s menstrual cycle after menarche?

A

Followed by 5-7 years of increasing regularity, and cycle shortening

9
Q

What is the usual length of flow for a woman’s menses?

A

4-6 days

10
Q

What happens in a woman’s 40s to her menstrual cycle?

A

Lengthen

11
Q

What is the normal volume of menses? Abnormal?

A

30 ml normal

more than 80 is abnormal

12
Q

Where does estrogen exert a negative feedback on the HPA axis?

A

At the level of the pituitary and the hypothalamus

13
Q

Where does estrogen exert a positive feedback on the HPA axis?

A

At the level of the pituitary

14
Q

What hormonal surge triggers ovulation?

A

LH

15
Q

What does the ovarian follicle turn into with ovulation? What is this responsible for?

A

Corpus luteum–responsible for secreting progesterone

16
Q

What chemical causes the corpus luteum to become yellow?

A

Lutein

17
Q

What is the embryology of the uterus? (cells involves, where they move, what germ layer, weeks gestation)

A

Primordial germ cells in the endoderm of the yolk sac migrate to the genital ridge by 5-6 weeks gestation

18
Q

The maximum number of oocytes is reached when?

A

16-20 weeks gestation

19
Q

What happens to the number of oocytes from gestation, birth, puberty, and reproductive years?

A

Gestational = 6 million
Birth =2 million
Puberty = 300,000
Reproductive years = Less than 500

20
Q

How many oocytes enlarge with each follicular phase?

A

Several

21
Q

What are the layers that surround each oocyte?

A

Granulosa cells and a membrane, the zona pellucida

22
Q

Follicular growth is dependent on what hormone? Where is the receptor for this hormone?

A

FSH–receptor is on the granulosa cells

23
Q

True or false: in the presence of FSH, the preantral follicle can aromatize androgens to estrogens

A

True

24
Q

What happens to the granulosa cells with FSH binding? Stromal cells?

A

Granulosa cells proliferation into multiple layers, and produce estrogen

Stromal cells differentiate into theca cells, to produce androgens

25
Q

What are theca cells derived from? Function?

A

Stromal cells derivatives–produce androgens for the granulosa cells to convert to estrogen for the developing follicle

26
Q

What is the graafian follicle?

A

Mature follicle

27
Q

What cells produce the estrogen to lay down the endometrial layer?

A

Follicular cells

28
Q

The follicles will only progress if what hormone concentrations exist?

A

FSH is elevated

LH is low

29
Q

The success of a follicle depends upon what?

A

Its ability to convert an androgen microenvironment to an estrogen one

30
Q

In the presence of (__) estrogen is the dominant substance.

A

FSH

31
Q

What happens to the oocyte if LH is prematurely elevated?

A

Androgen levels rise which antagonizes granulosa cell proliferation and promotes degenerative changes in the oocyte

32
Q

How do increased androgen levels inhibit oocyte proliferation? (2)

A
  • Antagonize granulosa cell proliferation

- Increased estrogen feedback on the HPA axis

33
Q

How does LH regulate steroidogenesis?

A

Regulates the entry of cholesterol into the mitochondria

34
Q

Granulosa cells initially have receptors for what hormone? What changes as it develops? Why?

A

Initially, only has FSH receptors, but gets LH receptors to be able to respond to ovulation

35
Q

When in the follicular phase do estradiol levels begin to rise? LH

A

Estradiol - Mid Follicular phase

LH - steadily rises during the late follicular phase, to stimulate androgen production in the theca cells

36
Q

What are the major preovulatory changes that occur to the follicle?

A
  • Granulosa cells enlarge and acquire lipids

- oocyte resumes meiosis

37
Q

Primary oocytes are arrested at which stage of meiosis?

A

diplotene stage of prophase I (the prophase of the first meiotic division)

38
Q

Estrogen levels peak how many hours prior to ovulation? Why?

A

24-36 hours to stimulate midcycle surge of LH

39
Q

What hormone promotes the luteinization of the granulosa cells? What happens when this occurs?

A

LH promotes granulosa cell luteinization, which results in progesterone production

40
Q

Prior to follicular progesterone production, the circulating level of progesterone was derived from where?

A

Adrenal gland

41
Q

When do progesterone receptors begin to appear on the granulosa cells?

A

Preovulatory follicle

42
Q

When the primary follicle grows, and the lesser follicles become atretic, the theca cells produce increased levels of androgens. What are the two major purposes of this?

A

Enhances process of atresia

Increases libido

43
Q

What happens to estradiol levels with the LH surge?

A

Plunge, then abrupt fall

44
Q

What hormonal surge stimulates the LH surge?

A

Estrogen

45
Q

Levels of which hormone can be measured at about day 21 to confirm that a woman has ovulated?

A

Progesterone

46
Q

What happens to progesterone levels in the luteal phase? How long does this last for? What is the effect of this?

A
  • Peak 8 days after LH surge, but stay elevated
  • Suppresses new follicular growth
  • consistently lasts 14 days
47
Q

How long does the corpus luteum survive for without implantation? What hormone can prevent this?

A

9-11 days

hCG will prevent luteal regression

48
Q

What is the effect of hCG on the corpus luteum?

A

Maintains steroidogenesis until 9-10th weeks of gestation

49
Q

What are the three endometrial phases of the ovulatory cycle?

A
  • Menstrual endometrium and proliferative phase
  • Ovulation
  • Secretory phase
50
Q

What is day 1 of the menstrual cycle?

A

First day of menstrual bleeding

51
Q

What is the role of prostaglandins in menstruation?

A

Induce uterine contractions

52
Q

What is the effect of the rise in estrogen levels in the early follicular phase?

A

Induces endometrial healing and cessation of menstruation

53
Q

What fraction of the endometrium may be lost during menstruation?

A

2/3

54
Q

What is the major layer of the endometrium that proliferates in response to estrogen?

A

Functionalis layer

55
Q

What are the hormone levels that limit growth of the endometrium during the uterine secretory phase?

A

Estrogen and progesterone

56
Q

Why are the vessels of the uterine lining coiled?

A

Progesterone limits the growth of endometrium, but estrogen encourages growth of vessels in this confined space

57
Q

What is the signal for endometrial breakdown?

A

Loss of estrogen and progesterone

58
Q

What happens to the endocervix in the menstrual cycle?

A

increased cervical mucus

59
Q

What happens to the breasts during the menstrual cycle?

A

TTP and fullness

60
Q

What happens to the vagina during the menstrual cycle?

A

Estrogen increases lubrication

61
Q

What happens to basal body temp with the menstrual cycle?

A

Progesterone increases basal body temperature just at ovulation

62
Q

Does tubal ligation have any effect on menstruation?

A

No

63
Q

What is the effect of hyper and hypothyroidism on menstruation

A

Hyper = short, quick bleeding

Hypo = prolonged, full bleeding

64
Q

What are the two hormones that regulate prolactin production?

A
Positive = TSH
Negative = dopamine
65
Q

What is the effect of prolactin on GnRH release?

A

Inhibits–therefore a prolactinoma will decrease estrogen/testosterone levels and interfere with menstruation

66
Q

What is the average duration of flow for menstruation? How much blood is lost? How much Fe is lost?

A

4 days
30 ml
13 mg

67
Q

What percent of blood loss during menstruation occurs within the first 2 days?

A

70%

68
Q

What is amenorrhea?

A

Absence of menstruation for 6 months

69
Q

What is polymenorrhea?

A

Uterine bleeding occurring at regular intervals of less than 21 days

70
Q

What is oligomenorrhea?

A

Cycle frequency of greater than 40 days, but less than 6 months

71
Q

What is primary amenorrhea?

A

Young woman who has never menstruated by age 13

72
Q

What is secondary amenorrhea?

A

Previously menstruating woman has not menstruated for 3-6 months

73
Q

What is menorrhagia?

A

Prolonged (greater than 7 days) of bleeding

74
Q

What is hypomenorrhea?

A

Cycle length of 2 days of less or reduction in flow

75
Q

What is intermenstrual bleeding?

A

Bleeding of variable amounts between regular periods

76
Q

What is metrorrhagia?

A

Bleeding at irregular, but frequent intervals of variable amount

77
Q

What is menometrorrhagia?

A

Frequent bleeding that is excessive and irregular in amount and duration

78
Q

What is the most common cause of amenorrhea?

A

Prego

79
Q

What are the functional causes of amenorrhea?

A

Excessive exercise or obesity

80
Q

True or false: most causes of amenorrhea (not 2/2 prego) are functional

A

True

81
Q

How do you assess for HPA axis dysfunction causing amenorrhea?

A

Measure FSH, LH, and prolactin levels

82
Q

What is the most common adenoma of the pituitary?

A

Prolactinoma

83
Q

Low FSH, LH, and estrogen/progesterone levels, suggests there is a dysfunction of what part of the HPA axis?

A

Hypothalamus or pituitary–check GnRH to see

84
Q

High FSH/LH, but low estrogen/progesterone suggests there is a dysfunction of what part of the HPA axis?

A

Ovaries

85
Q

Turner’s syndrome can have what effect on the HPA axis?

A

Ovaries will not function correctly–streak ovaries

86
Q

What is asherman syndrome?

A

a condition characterized by adhesions and/or fibrosis of the endometrium particularly but can also affect the myometrium. It is often associated with dilation and curettage of the intrauterine cavity

Can cause amenorrhea

87
Q

What is the most frequent anatomic cause of secondary amenorrhea?

A

Asherman syndrome

88
Q

What is the treatment for Asherman’s syndrome

A

Surgical lysis of adhesions by hysteroscopy

89
Q

What is the hormone that heals the uterine lining?

A

Estrogen

90
Q

What is the thinking behind the progesterone challenge test for assessing amenorrhea?

A
  1. Assess if pt has adequate estrogen, competent endometrium, and genital outflow tract.
  2. Induce progesterone withdrawal bleed within one week of oral progesterone
  3. If bleeding occurs, pt anovulatory. If no bleeding, hypoestrogenic or anatomic
91
Q

What are the s/sx of a prolactinoma?

A
  • Galactorrhea

- Amenorrhea

92
Q

What is the medical treatment for a prolactinoma? MOA?

A

Bromocriptine–Dopamine agonist

93
Q

How can ovulation be induced if a patient has amenorrhea?

A
  • Clomiphene citrate
  • Human menopausal gonadotropins
  • Pulsatile GnRH
  • Aromatase inhibitors
94
Q

How will aromatase inhibitors cause ovulation?

A

Increases in estrogen levels will cause lH surge etc

95
Q

What causes the abnormal bleeding with anovulatory patients?

A

Continued release of estrogen builds up uterine lining, but there is no pause in estrogen to stop it

96
Q

What causes the abnormal bleeding with patients who have a luteal phase defect?

A

Corpus luteum does not produce enough progesterone to maintain the uterine lining. Results in shortened luteal phase, and infertility

97
Q

What is midcycle spotting? Is this concerning?

A

Bleeding at the time of ovulation–in the absence of other pathology, then is a self-limited benign condition

98
Q

When should you suspect AUB?

A

Irregular, unpredictable, and not associated with PMS s/sx

99
Q

What are the conditions that you must exclude with AUB?

A
  • Neoplasia
  • pregnancy
  • Anatomical issues of vagina
100
Q

How do you diagnose AUB caused by unopposed estrogen stimulation?

A

endometrial bx

101
Q

What is the treatment for AUB? (2)

A
  • Progestin for 10-14 days to mimic withdrawl of progesterone
  • Combination oral contraception
102
Q

What is the MOA of oral combination contraceptives in treating AUB?

A

Suppresses the endometrium and also establishes a regular withdrawal cycle

103
Q

What is the MOA of progestin for treating AUB?

A

10-14 days of progestin mimic the fall of progesterone, causing uterine lining shedding

104
Q

What is the medical treatment for acute, heavy abnormal bleeding?

A

HIgh dose estrogen and/or progesterone, follow by preventative management with oral contraceptives

105
Q

What should be done if medical treatment for acute heavy AUB fails?

A

D and C