Female Reproduction And Menopause Flashcards
1
Q
When do we start calling an embryo a fetus
A
After 2 months of development
2
Q
What does estrogen do?
A
Secondary sexual characteristics
Ova maturation and release
Primes tissue to progesterone by increased progesterone receptors
Contributes to transport/viability of sperm in female
Breast development for lactation
3
Q
What does progesterone do
A
Prepares uterus for nourishment of embryo
Contributes to breasts’ ability to produce milk
4
Q
When do primordial germ cells go through mitosis?
A
Before birth until 20-24 weeks gestation! 6-7 million are made.
5
Q
What happens to the oogonia that are produced until you’re a 20-24 week old fetus?
A
They enter prophase 1 of meisois 1 and then they just STOP UNTIL PUBERTY**
Yes that’s right, meiosis 1 doesnt even finish until puberty
6
Q
When does meiosis 1 resume?
A
Just before ovulation, and ONLY in the oocyte that is released.
7
Q
When you’re a little fetus, you make 7 million oogonia. How many are you born with?
A
Most of them degenerate before birth and then continue to degenerate.
By puberty only 400,000 remain, and over your lifetime, only 400 are ovulated
8
Q
When does meiosis 1 complete?
A
Just prior to ovulation
9
Q
When does meiosis 2 complete?
A
After fertilization
10
Q
How many mature ovums will come from a primary oocyte?
A
Only 1. During the divisions, the cytoplasm is divided unevenly so only one gets it and the rest are polar bodies.
11
Q
What stage is the egg in when the sperm first touches it?
A
Secondary oocyte.
Does not complete oogenesis and become an ovum until the sperm entry triggers the second meiotic division.
12
Q
Oogenesis completes ONLY if the woman ________
A
Gets knocked up
13
Q
Each primary oocyte yields ____ cytoplasm rich ovum and _____ cytoplasm-devoid polar bodies
A
1 ovum
3 polar bodies
(Vs each primary speratocyte yielding 4 equally viable spermatozoa)
14
Q
Are the ovarian cycle and uterine cycle the same thing
A
No
15
Q
When is the follicular phase?
A
Day 1 to ovulation
16
Q
When is the luteal phase?
A
Ovulation to the beginning of mesntruation
17
Q
How many layers of granulosa cells are in a primary follicle?
A
Single layer
18
Q
What causes the granulosa cells of primary follicle to proliferate and form a zone pellucida, as well as cause surrounding ovarian connective tissue to become the thecal cells?
A
Local paracrines
19
Q
Once a follicle reaches the preantral phase, what happens?
A
FSH at the beginning of the follicular phase recruits them to develop into an antral/secondary follicle as an estrogen-rich antrum starts to form
20
Q
What is a Graafian follicle?
A
A completely mature follicle that has been growing rapidly under the influence of FSH.
It has a large antrum and the secondary oocyte is displaced to one side.
21
Q
What causes the mature Graafian follicle to rupture and release the oocyte (ovulation)
A
LH surge
22
Q
What causes the ruptured follicle to develop into a corpus luteum?
A
LH
23
Q
What does the corpus luteum secrete?
A
Progesterone and Estrogen to prepare the uterus for implantation
24
Q
What happens to the corpus luteum if a fertilized ovum doesnt implant within 14 days?
A
Corpus luteum will degenerate, the luteal phase will end, and a new follicular phase begins
25
What is the zone pellucida?
A gel-like substance that surrounds the oocyte. (Secreted by granulosa cells)
26
What hormones cause a primordial follicle to develop into a preantral follicle?
NONE!!!! It is hormone-independent
27
How many ooytes get to complete meiosis 1 each month
1
28
What happens to the levels of estrogen throughout the follicular phase?
Increase
| Granulosa and thecal cells secrete increasing amounts as the follicle nears ovulation
29
What is the ONLY hormone produced by the follicle
Estrogen
| Changes AFTER it develops into a corpus luteum
30
What does corpus luteum mean?
“Yellow body” due to all the cholesterol in it that it uses to make PROGESTERONE
31
What is a degenerated corpus luteum called?
Corpus albicans. “White body” due to fibrous tissue
32
What hormones are secreted by the corpus luteum?
Estrogen
Progesterone
33
Which follicular cells convert cholesterol to androgens?
Theca cells ONLY
| They are the only ones with cholesterol desmolase
34
What hormone causes cholesterol desmolase to start converting cholesterol to androgens?
LH
35
Which follicular cells convert androgens to estradiol?
Granulosa cells***
| They are the only ones with aromatase enzyme.
36
What hormone causes the granulosa cells to convert androgens (mostly androstenedione) into estradiol?
FSH****
37
Cholesterol desmolase is in ______ cells and is stimulated by _____
Aromatase is in _____ cells and is stimulated by _____
Theca, LH
Granulosa, FSH
38
What happens to the estrogen produced by the granulosa cells?
Some of it is released into the blood to exert systemic effects (coupled to carrier proteins)
Some of it remains in the follicle and contributes to antral formation
39
What stimulates the continued proliferation of the granulosa cells?
Local estrogen along with FSH
40
How much of the circulating estrogen is free vs bound to plasma proteins? Does it change throughout the menstrual cycle?
Only 3% is free and this does NOT change during the menstrual cycle. (Doesn’t matter how much is being made in the ovary)
41
GnRH is released in a (constant/pulsatile) manner
Pulsatile
42
FSH Gonadotropes are stimulated by (high/low) pulse frequency of GnRH
Low***
43
LH gonadotropes are stimulated by (high/low) pulse frequency of GnRH
high***
44
What causes Inhibin to be released from granulosa cells?
FSH
45
Where does inhibin come from
Granulosa cells
46
What effect does inhibin have
Negative feedback on FSH!***
47
What kinds of things will inhibit the release of GnRH?
Prolactin
Stress
Exercise
Endorphins
Chronic illness
48
At ovulation, estrogen levels are (high/low)
High**
49
What causes the LH surge?
The estrogen level that has been climbing higher and higher through the follicular phase suddenly reaches a magic threshold and switches from having a negative feedback to a POSITIVE feedback on the hypothalamus and pituitary.
Hypothalamus: increased GnRH frequency
Pituitary: increased GnRH receptors
50
Why does only LH surge at ovulation? Estrogen is stimulating GnRH release, so shouldn’t it be both LH and FSH?
FSH does not rise as much die to INHIBIN!!!!*****!*!*!*!**!*!*!*
51
What are the effects of the LH surge?
Conversion of antral follicle to Graafian follicle
Process of meiosis is resumed
Production of protelolytic enzymes in follicle (digestion of follicle for ovulation rupture)
Increase prostaglandins- increase follicular blood flow, wall distensibility, and proteolytic enzymes
Differentiate follicle cells into corpus luteum **Luteinization**
52
Once the follicle has turned into a corpus luteum, what prevents another LH surge?
The Progesterone that is now coming from the corpus luteum!
53
How does progesterone prevent another LH surge?
It has a negative* feedback effect on the hypothalamus, which suppresses the positive feedback of estrogen, preventing another LH surge
54
Ok so progesterone has now suppressed the release of FSH and LH. Now what?
The low LH causes the corpus luteum to degenerate, progesterone levels decline, and FSH levels can start to rise again, initiating a new cycle
55
Estrogen normally has a negative feedback on the anterior pituitary. When does it have a positive effect?
**midcycle**
56
What hormone restores the negative feedback of estrogen on the anterior pituitary
Progesterone**
57
What are the 3 phases of the Uterine cycle?
Menstrual phase days 0-4
Proliferative phase days 5-14
Secretory (progestational phase) days 15-28
58
Your period ALWAYS starts exactly 14 days after ovulation, so if you don’t have a perfect 28 day cycle, which ovarian is longer/shorter
Follicular
59
What do the prostaglandins released by the uterus during menstruation do?
Vasoconstriction of endometrial vessels which disrupts blood supply and results in death of endometrium
Stimulates mild rhythmic contractions of uterine myometruim to expel blood from uterus
60
When does the proliferative phase begin
Last portion of ovarian follicular phase
61
What happens during the proliferative phase?
Endometrium repairs itself and proliferates under the influence of estrogen from newly growing follicles
62
How long does the estrogen-dominant proliferative phase last?
Until ovulation
63
When does the secretory/progestational phase happen?
After ovulation when a new corpus luteum has formed
64
What happens during the secretory/progestational phase?
Progesterone converts the endometrium to highly vascularized, glycogen-filled tissue
Endometrial glands actively secrete glycogen
65
What hormone causes the uterine lining to become highly vascular?
Progesterone
66
What causes the breakdown and shedding of the uterine lining?
Withdrawal of hormone support
67
What hormone causes the endometrial lining to thicken (not vascularize)
Estrogen
68
What are the effects of estrogen on a woman’s body other than the menstrual cycle
Heart- protects from cholesterol
Liver- reduces cholesterol in blood
Vagina- makes it moist, protects from infection
Brain- adjusts body temp, increases memory, libido
Breast- grows and shapes breast, prepares breast for feeding
Skin- “makes skin young”
Bone- strengthens bone, increases density
69
What are the effects of estrogen on the Fallopian tubes?
Increases number of cilia and their rate of beating to help the ovum go INTO the tube
70
What are the effects of estrogen on the uterus?
Myometrium- increases oxytocin receptors and contractions
Endometrium- thickens, increases permeability. **Synthesizes receptors for progesterone on uterine cells***********
71
What are the effects of estrogen on the cervix?
Makes mucus thin, watery, and alkaline
Increases distensibility to make birthing easier
(@ midpoint of cycle, vagina becomes more friendly for sperm)
72
What are the effects of estrogen on the vagina?
Proliferation of the epithelial layer
Increases vaginal secretions (reason menopause causes atrophy and dryness of vagina)
73
What are the effects of estrogen on the mammary glands?
Required for growth
Increases ductal growth and growth of breast
Increases nipple size and pigmentation
(Every month there’s growth, nipple changes and sensitivity changes)
74
What hormone causes increased deposit of subcutaneous fat in the hips and breasts
You bet its estrogen
75
What are the effects of estrogen on the skeletal system and calcium metabolism
Epiphyseal closure
Facilitates calcium uptake into bone
Antagonizes PTH on bone (decrease rate of resorption)
Inhibits osteoclasts
76
What are the effects of estrogen on the skin/hair growth?
Inhibits body and facial hair growth (except for pubic and armpit hair)
PROMOTES pubic and armpit hair growth
*******WAS IN RED***
77
What are the effects of estrogen on the kidneys?
Increases absorption of Na+, Cl- and H2O, which contributes to bloating during the menstrual cycle***********WAS IN RED
78
What are the effects of estrogen on the heart?
Maintains low blood cholesterol (high HDL, low LDL)
Arterial vasodilator
Decreases atherosclerosis
79
What “primes” the uterus for sitimulation by progesterone?
ESTROGEN!!**!**!*!*!*!**!*!*!**!*!*!*!**!*!* THIS WAS RED AND HAD EXCLAMATION POINTS
80
What are the effects of progesterone on the uterus?
Increase development of endometrial glands, converts uterus into actively secreting tissue
Induces deciduous formation
Decreases contractility
81
What are the effects of progestoern on the cervix?
Antagonizes Estrogen **!*!*!*
Decreases distensiibilty
Thick acidic mucus
(we don’t need a friendly environment for sperm anymore after ovulation!)
82
What are the effects of progestoern on the vagina?
ANTAGONIZES ESTROGEN!**!**
Decreases proliferation of epithelial layer
83
What are the effects of progestoern on the mammary glands?
Increased branching of the ductal system
Stimulated development of lobules and alveoli
84
What are the effects of progesterone on body temp and appetite?
Increased temperature following ovulation by 0.5 degrees C (used as an indicator that ovulation has occurred)
Increases appetite
85
What are the effects of progesterone on the kidneys?
Decreases Na+ reabsorption by competing with aldosterone
| No more bloating after ovulation. Reverses effects of estrogen
86
What is the hormone of pregnancy, that is responsible for implantation of the zygote and maintenance of the pregant state?
Progesterone
87
Progesterone acts on estrogen primed tissues and typically (agonizes/antagonizes) estrogen’s effects
Antagonizes
88
What causes contractions of the uterus that cause menstrual cramps?
Prostaglandins (reasons NSAIDs help)
89
When do mesntrual cramps happen
When your period starts
90
PMS happens in the (luteal/follicular) phase
Luteal
91
What is Premenstrual Dysphoric Disorder (PMDD)?
PMS symptoms related to severe mood disorder:
Bloating
Weight gain increased appetite
breast tenderness
Ankle edema
Headaches
Irritability and mood swings
Depression/anxiety
Fatigue
Difficult concentrating and working effectively
92
What is menopause?
A decline in fertility associated with a decline in ovarian function
93
What causes menopause
Drop in the critical mass of primordial follicles
94
What is the mean age of menopause?
51.4 years******
Range: 40-58yrs
95
When does follicular atresia accelerate RAPIDLY in a *climacteric* fashion
37.5 yrs*****
**preprogrammed accelerated dwindling of follicle pool**
96
What is the PRIMARY cause of perimenopause/menopause
DECREASED FOLLICLE POOL
97
At the beginning phase of perimenopause, when your follicle pool is starting to get smaller you have a shorter menstrual cycle. Why?
Follicles making less inhibin = increased FSH = more and more follicles mature faster and faster = shorter cycle
98
In the middle phase of perimenopause, when your follicle pool is even smaller, why do you have a longer cycle?
Decreased estrogen = delayed positive feedback = longer cycle
99
What happens if your follicle pool is so small that you start to have insufficient estrogen to cause a positve feedback?
No LH spike = NO ovulation
100
When you have like basically NO follicles left and no estrogen, what happens to LH and FSH levels?
They get SUPER HIGH.
There will be no negative feedback of estrogen on the hypothalamus so LH and FSH will be released in super high amounts
101
What hormone levels could you check to diagnose menopause?
FSH (maybe LH too?) since they will be extremely high once the woman has no follicles making estrogen aka menopause
102
What levels of FSH are diagnostic for menopause?
FSH >30 mIU/mL***
Was in a red box*
103
What are the effects of menopause on the body?
Hot flashes (no more temp regulation)
Urogenital atrophy (atrophy or estrogen dependent tissues: breast, uterus, vagina)
Decreased vaginal secretion, painful sex
Cognitive function- increased risk of Alzheimer’s
Osteoporosis
Cardiovascular disease
104
What is the mechanism of action of hormonal contraception?
Prevents ovulation by NEGATIVE feedback on the anterior pituitary, preventing LH surge!!!!****
Also:
Thickens cervical mucus
Decreased motility of uterus and Fallopian tubes
Decreased uterine glycogen production, which impaired blastocyst survival and interferes with implantation
105
What hormones are in birth control?
Can be combination pills with E and P or...
Progesterone alone
