Week 13 Female Reproductive System Flashcards
Whats proliferating are the cells that make up the?
stratum compactum and stratum spongiosum, and the glands in stratum spongiosum and spiral arteries in stratum spongiosum
at the end menstruation, thickness of endometrium was about half a milimeter but by the end of the proliferative phase, how thick is it?
2-3 mm
- all of that increase in thickness is due to adding cells
- the cells are proliferating and that is what’s making the endometrium thicker there
the proliferative phase is followed by ?
ovulation
- not a span of time, it is an event
after ovulation, our spinal phase is going to lead to ?
a bigger increase in the thickness of endometrium
that thickness increase thats under the control of progesterone is mostly due to?
endometrium retaining fluid
progesterone levels drop, spiral arteries spasm, and then we will return to where we started which was?
the beginning of the cycle of menstruation
MORE IN DEPTH:
first part of cycle approximately how long?
Day 1 to Day 5 is menses (menstruation)
- all about getting rid of the old endometrium or old stratum compactum and stratum spongiosum to build a newer and fresher compactum and spongiosum
Menses is followed by a phase that has many names:
- post menstrual phase (which tells you what’s happening with the endometrium)
- pre ovulatory phase (bc the next phase is ovulation)
- estrogenic phase (main hormone in this phase of menstrual cycle is estrogen)
- follicular phase (granulosa cells of the follicle that are making the estrogen)
- proliferative phase (stratum compactum and spongiosum cells are proliferating and thats whats causing thickness)
how long is this phase?
day 6 to day 13
- most variation
- in a woman who has longer overall cycle, this phase tend to be longer than one who has a shorter cycle
what’s going on here?
we’re proliferating cells that thicken the endometrium, estrogen levels go up and that’s gonna cause the endometrium glands and cervical mucus glands to secrete things that tend to block the passage of sperm
why would you want to block the passage of sperm at this point?
if you haven’t ovulated yet, there’s nothing to fertilize, the menstrual cycle is about effective use of resources so you can use the most possible resources to support a full pregnancy
- sperm can live 2-3 days in female reproductive tract and so anything that arrives more than 2-3 days before ovulation or after is something else to get rid of so we tend to block it
glands are growing and spiral arteries are growing
the next phase is ovulation and in the mythical 28 day cycle, this would be on day?
day 14
what is ovulation?
the rupture of a follicle in the release of an egg into the fallopian tubes
- before we had OTC kits to test for ovulation, we used to look at basil body temp for an indication of ovulation (basil body temp is absolute resting body temp when you have done nothing)
- if woman is tracking body temp to see if shes ovulating, grabs thermometer to see temp with no coffee, bathroom breaks, immediately upon waking up.
- before she ovulated, the temp will drop a little bit
our last phase that will take us back to menses is ?
Day 15 to Day 28
- post ovulatory
- premenstrual
- proliferative
- gluteal (corpus luteum is now the endocrine structure thats driving this. previously it was hormones being produced by granulosa cells of follicle, not its corpus luteum)
- progesterone (big hormone from corpus luteum is progesterone)
- secretory (corupus luteum is secreting a whole bunch of hormones that are all having the same goal: create the most supportive conditions for pregnancy from preceeding ovulation)
whats happening here?
progesterone levels go up cause us to increase thickness of myometrium, primarily by holding onto fluid.
- body temp goes up bc progesterone makes body temp go up
from the time the one follicle thats supposed to rupture ruptures, and we have ovulation, we start formation of?
corpus luteum
- now we’re getting a lot of progesterone, some estrogen, also inhibin and relaxin
very little variability in this phase bc?
it takes 7 days to develop a fully functioning luteum and takes about 7 days for it to die off
- as corpus luteum dies off, progesterone levels are dropping and hit a critical level that causes a spasming of spiral arteries and here we go again: we cut off blood supply to stratum compactum and spongiosum and they die and we shed and then back to menstruation
FUNCTIONS OF UTERUS:
1) where do most fertilization (conception) happen in?
fallopian tubes
- the rest of it that doesn’t lead to ectopic pregnancy happens in uterus (also site of implantation)
2) uterus is also site of implantation and bc of that, its gonna be a source of?
nutrients for developing embryo and fetus
the secretions of uterine glands is an early source of?
nutrients once a placenta is developed, the maternal blood supply in the uterus is gonna be the source of nutrients
3) contractions of myometrial is gonna help with?
expelling fetus at end of gestation
4) uterus has an important role in menstruation, not just in the shedding of endometrium but also?
myometrial activity, to help break endometrium so its easier to shed, we have myometrial contraction which causes myometrial to fatigue causing menstrual cramps
what is the beginning of the cycle of women?
Menarche
- 1st menstrual flow
- definition of onset puberty in a female