Ovarian Function Flashcards
3 phases of menstrual cycle
follicular: 1-13
ovulation: 14
luteal: 15-28
3 phases of endometrial lining?
menses - shed
proliferative phase
secretory phase: promotes implantation
2 characteristics controlled by estrogen?
breast development
body fat distribution
what does adrenal androgens do to females? 2 things
pubic and axillary hair
libido
cervix is normally?
long
thick
closed
Granulosa cells secrete?
estrogen before ovulation
progesterone after ovulation as corpus lutem
When is the second meiotic division completed in the oocyte?
AFTER fertilization
What happens to Copus luteum if no preganancy?
degenerates into corpus albicans
What is the role of thecal and granulosa cells in follicle maturation?
LH>thecal cells>androgens>Granulosa cells>aromatase>estrogens>+ve feedback develops follicle and increase estrogen>-ve feedback decreases FSH+LH
what causes LH surge?
high estrogen from granulosa cells +ve feedback to hypothalamus, increased GnRH
Inhibin does what?
inhibits FSH so there is not a new follicle produced
what does low progesterone do in late follicular phase?
+ve feedback on GnRH and LH to promot LH surge
when does primary oocyte complete its first meiotic division?
before ovulation in late follicular phase during high estrogen
what happens to follicle after ovulation
decrease estrogen
morph into luteal cells
estrogen and progesterone levels in luteal phase? where is it coming from?
increased to maintain endometrium
comes from corpus luteum
GnRH, LH, FSH levels in luteal phase?
low
inhibin levels in luteal phase?
high to inhibit follicle develment
cervix during ovulation?
abundant clear non viscous (let sperm in)
cervix in mid-luteal phase?
thick sticky viscous because no need for more sperm
uterus in mid luteal phase?
vascular and secretory
Late luteal phase corpus luteum in preg vs. non-preg:
preg: corpus luteum maintained
non-preg: corpus luteum degens, decreasing estrogen and prog. and triggers menses,
Menses hormone levels do what to hypothalamus?
low estrogen and progesterone means loss fo -ve feeback to hypothalamus so you get higher FSH, LH and new follicle
3 causes of menopause?
- no more egg development
- ovaries cease responding to LH/FSH
- low estrogen and progesterone
menopause symptoms?
hot flashes
osteoporosis
sperm live how long in vagina?
oocyte viable for how long?
- 48 hours for sperm
2. 24 hours for oocyte
what happens when sperm reaches oocyte in fallopian tube?
acrosomal reaction causes digestive enzymes and the zona pellucida and cell junctions dissolve
what blocks polyspermy?
cortical reaction after sperm and egg membranes fuse
what is a sperm called that reach zona pellucida?
capicitated sperm
second polar body ejected from?
ZYGOTE
what day post-fertilization does blastocyst implant?
days 5-9
completely buried
what is a decidualized endometrium?
becomes more vascular and changes to adapt to implanted blastocyst
when is:
Early Preg?
Embryonic period?
fetal period?
Early Preg: 1-2 weeks
Embryonic period: 3-8 weeks
fetal period: 9-term
early preg is susceptible to?
chromosome abnormalities
environmental prevent implantation
early preg is non susceptible to?
teratogens
when are baby most susceptible to teratogens?
embryonic week 3-8
all major organ systems formed when?
by end of embryonic week 3-8
when do you get most physiological defects in preg?
fetal period
Conception has 3 strategies to modify:
Ovulation -endocrine OCP Sperm -ovum transport (barrier, surgery) Prevent implantation (IUD)
how does OCP work?
lose dose estrogen and progesterone doesn’t allow -ve feedback to hypothalamus to make FSH or subsequent LH surge. and no endometrium development either