Menstrual Cycle Flashcards
Around what age does the menstrual cycle typically end?
around age 50
Around what age does the menstrual cycle begin?
around age 11-13
How long does a menstrual cycle last?
Typically 28 days from first day of bleeding
varies from patient to patient
What regulates the menstrual cycle?
the hypothalamus
dependent upon cyclic release of estrogen and progesterone from ovaries
What is Premenarch?
prepuberty - prior to the onset of menses
What is Menarch?
after reaching puberty
menses occurs normally every 28 days (1st menses to menopause)
What is menopause?
the cessation of menses
What are the menstrual statuses?
Premenarch
Menarch
Menopause (no period for one solid year)
What are the gonadotropins?
Hormonal substance which stimulates the function of the testes and ovaries
What hormones do the gonadotropins release?
FSH (follicle stimulating hormone)
LH (luteninizing hormone)
LTH (luteotropic hormone)
Estrogen
Progesterone
What is Estrogen?
Steroid
Released by theca interna and granulose cells of ovarian follicle
promotes growth of endometrium durning menstrual cycle
What is ovulation?
explosive release of ovum from ruptured graafian follicle
what is an oocyte?
primordial or incompletely developed ovum
who regulates ovulation?
the hypothalalmus
What does the Anterior Pituitary gland do?
secretes varying levels of gonadotropins (FSH, LH, LTH)
What is the first half of the menstrual cycle called?
proliferative, follicular or estrogenic phase
When is the first half of the menstrual cycle?
usually days 1-14 may vary in length accounts for shortere or longer menstrual cycle
What happens on day 1 of the first half of the menstrual cycle?
first day of bleeding ( menstrual flow)
What happens day 1 through day 4-5?
estrogen levels decreases
FSH releases/stimulates follicular growth and maturity
What happens day 4-5 of the first half of the menstrual cycle?
menstrual flow complete
endo lining ready for new growth (proliferation)
What happens day 5-14 of the first half of the menstrual cycle?
follicles grow
what is a mature follicle called?
a graafian follicle
What does estrogen trigger?
new growth of endometrial lining (proliferation)
When does ovulation occur?
approx day 14
What is the lutenizing surge?
LH surge peaks 10-12 hours prior to ovulation - used for ovulation prediction for conception
What released the egg, who catches it?
Released by: Graafian follicle
directed by fimbria into the infundibulum of the Fallopian tube.
Where would you find fluid after the follicular rupture?
usually associated with release of fluid into posterior cul-de-sac
What is Mittleschmerz (middle pain)
fluid causes irritation to membranes (fluid from released ovum during ovulation…this is normal)
causes pain during ovulation
What is the second half of the menstrual cycle called?
pro-gestational, luteal or secretory phase
What is the measurement for a follicle?
2-2.5 cm
what is the measurement for an ovarian cyst?
2.5cm or bigger
When does the second half of the menstrual cycle begin?
begins with ovulation
lasts approx 14 days
does not vary in length
What happens during the second half of the menstrual cycle?
follicle ruptured - corpus luteum
what does corpus luteum mean?
Yellow body
how is the endometrium affected by the ovulatory cycle?
affected by varying levels of progesterone and estrogen
what are the three phases of the menstrual cycle that affect the endometrium?
the menstrual phase
proliferative phase
secretory phase
what is the menstrual phase?
decreasing progesterone levels
spiral arterioles constrict
zona functionalis ischemia - shedding
what is the proliferative phase?
days 6-14
lasts until ovulation
lasts until luteinization of Graafian follicle - ovulation
what happens to the superficial layer of the endometrium during the proliferative phase?
it regenerates and grows
follicles regrow with FSH stimulation (estrogen rises)
what is the periovulatory phase or late proliferative?
days 10-14
endometrium triple layer appearance
slide 25 finish
When is the secretory phase?
15-28 days or the on set of menses
when the person starts to bleed
what happens during the secretory phase?
the thickest point of the endometrium*
progesterone secreted by ovary
spiral arteries and endometrial glands enlarge
finalizes endometrial lining for implantation if fertilization occurs
What is an anovulatory patient?
birth control users or post menopausal or prepubescent
endometrium is thin and has an echogenic line
birth control will be <5mm
What does a postmenopausal endometrium NOT on hormone replacement therapy measure?
endometrial thickness <5mm
a thickened endometrium with no HRT and bleeding can be cancer so know this!!
what is menorrhagia?
abnormally heavy or long periods
associated with fibroids, IUd, hormonal imbalance
can lead to anemia
What is oligomenorhea?
abnormally short or light periods
associated with polycystic ovary syndrome (POS)
emotional/physical stress, chronic illness, tumors secreting estrogen, poor nutrition, eating disorders, heavy exercise
what is polymenorrhea?
cycle occurs at intervals of <21 days
what is dysmenorrhea?
painful periods (severe pain)
associated with endometriosis (the endometrium outside the uterus goes through the same changes as the stuff inside)
what is Amenorrhea - primary?
absence of menstruation
delayed beyond 18 yr old
due to:
ovarian dysfunction
pituitary disease
other endocrine disturbances
what is amenorrhea - secondary?
cessation of menstruation in women who previously menstruated
due to:
congenital vaginal or cervical stenosis
infection
trauma
pituitary disease
other endocrine distrubances
What is progesterone?
Produced by corpus luteum
prepares and maintains endometrium for arrival and implantation of embryo
What does FSH do?
Causes follicle to develop during first half of menstrual cycle
estrogen level rises with follicle maturation
what does LH do?
triggers ovulation
what does LTH do?
maintains corpus luteum
what is a steriod?
chemical which stimulates growth or maturation
What two steroids are produced in the female body for menstruation?
Estrogen
progesterone
What is Progesterone?
Steroid
produced by corpus luteum
Prepares and maintains endometrium for arrival and implantation of embryo
During ovulation how often in an ovum released?
Monthly
when does ovulation occur in the month?
occurs midcycle
day 14 of a 28 day cycle
When is the ovum released from each left or right ovary?
ovulation alternates monthly between the two ovaries
At what stage of life does a female begin developing ova?
development begins during embryonic life
How many oocytes will a female have at the time of birth?
approx 200,000
How does the hypothalamus regulate ovulation?
releases gonadotropin releasing hormones (GnRHs)
During ovulation what gland does the hypothalamus stimulate?
the anterior pituitary gland
What does FSH (follicle stimulating hormone) do during ovulation?
causes follicle to develop during first half of menstrual cycle
what happens to the estrogen level during follicle maturation?
it rises
What does LH (lutenizing hormone) do during ovulation?
triggers ovulation
What does LTH (Luteotropic hormone) do during ovulation?
maintains the corpus luteum
What happens to estrogen production during the first half of the menstrual cycle?
decreased - no pregnancy
What does the anterior pituitary gland do during the first half of the menstrual cycle?
secrets FSH
What does FSH do during the first half of the menstrual cycle?
stimulates ovarian follicles to grow and mature
What happens on day 5-8 of the first half of the menstrual cycle?
follicles begin to develop
What does a follicle do when it develops in the first half of the menstrual cycle
days 5-8
the follicles fill with fluid
secrete increasing amounts of estrogen
What happens to FSH levels during day 5-8 of the first half of the menstrual cycle?
FSH level decreases
In the first half of the menstrual cycle what is the follicle called that reaches maturity around day 14?
a Graafian follicle
Describe the Graafian follicle on day 14 of the first half of the menstrual cycle…
usually only 1 follicle reaches maturity
approx 2 cm in diameter
What does estrogen do during the 5-14 days of the first half of the menstrual cycle?
triggers new growth of endometrial lining (proliferation)
What does the corpus luteum release during the second half of the menstrual cycle?
progesterone
What happens to the basal body temperature during the second half of the menstrual cycle?
body temp increases
Is LTH released in the first or second half of the menstrual cycle?
LTH is released in the second half of the menstrual cycle
What happens in the second half of the menstrual cycle if the ovum is released?
hCG is released
What happens in the second half of the menstrual cycle if the ovum is NOT fertilized?
Menses will occur
What happens to the corpus luteum if the ovum is not fertiziled?
it gradually decreases after 9 days
What happens on day 25-26 of the second half of menstrual cycle if fertilization has taken place?
9-11 days after ovulation
hCG (human chorionic gonadotropin) produced by zygote
corpus luteum persists (maintained by LTH) and secrets progesterone for three months until placenta takes over. corpus luteum gradually dissolves
What happens on day 25-26 of the second half of menstrual cycle if no fertilization occurs?
9-11 days after ovulation…
If no fertilization occurs:
LTH subsides
corpus luteum degenerates
progesterone levels drop
menstruation begins
What happens to the spiral arteries on day 25-26 of the second half of the menstrual cycle?
spiral arteries contract due to decreased progesterone and estrogen
blood supply to inner 2/3 of endometrium is cut off which creates endometrium necrosis and then it sloughs off
what happens on approx day 28 of the second half of the menstrual cycle
decreased estrogen
increased FSH
process starts again
What correlates with the ovulatory cycle of the ovary?
Endometrial changes….which also correlates with patients menstrual status
What ovarian cycle phase coincides with the menstrual phase?
the follicular phase of the ovarian cycle
How long does the menstrual phase last?
Lasts approx 1-5 days
What does the endometrium look like during the menstrual phase?
thin line…late in the menstrual phase
What does the proliferative phase prepare the endometrium for?
the endometrium is prepared for implantation
During the proliferative phase, how does the endometrium look?
the endometrium is in it’s 3 line phase
average measurement is 4-8mm
made of the zona basalis A &P and the uterine cavity creates the central line
In the proliferative phase, what is the thickened three line?
The endometrium thickens and three lines are able to be seen
occurs late in the phase - ovulation
average measurement is 6-10mm
appears isoechoic to myometrium
The secretory phase corresponds to which ovarian phase?
the luteal phase of the ovary
What happens to the endometrial lining during ovulation?
It continues to grow because of the stimulation of increasing estrogen levels
What does an increased level of estrogen trigger during ovulation?
release of LH from the anterior pituitary gland
What does LH do during ovulation?
rapidly increases over a 24-36 hour time period
triggers ovulation
What is the measurement for a postmenopausal endometrium for a patient taking HRT or tamoxifen (ta MOX a phen)?
endometrium up to 8mm
What are the measurements of the endometrium during the secretory phase?
average 7-14 mm
thick endometrium with posterior acoustic enhancement
becomes echogenic
