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Flashcards in GYN- Amenorrhea Deck (11)
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how to define 1/1 and 2/2 amenorrhea

1/1: absence of menarche by age 16 or 4 yrs after thelarche

2/2: absence of menses for 6 mos, had periods at one time


what are the 3 types of etiologies of 1/1 amenorrhea?

outflow tract obstruction
end organ disorder
central regulatory disorder


what are the outflow tract obstructions that can cause 1/1 amenorrhea?

- imperforate hymen
- transverse vaginal septum
- MRKH syndrome (mullerian agenesis or dysgenesis= lack of uterus and upper vagina)
- vaginal atreasia
- androgen insesitivity syndrome (mut T receptor --> 46, XY female with blind pouch vagina)


what are central regulatory disorders that can cause 1/1 amenorrhea?

something wrong with GnRH or FSH/LH release

- kallmann syndrome: lack arcuate + olfactory nuclei (no GnRH release + anosmia), Dx olfactory challenge, Tx exogenous GnRH (pulsatile)

- Craniopharyngioma: rathke's puch tumor --> pituitary compression, Dx supracellar calcified cysts


What are end organ disorders that can cause 1/1 amenorrhea?

ovaries will not respond to FSH/LH

- Savage syndrome: mut FSH/LH receptor
- Turner's syndrome: rapid ovarian atresia --> streak ovaries w/o oocytes left
- 17a hydroxylase def: cannot produce T but still have MID -->< 46, XY female with blind pouch vagina
- Swyer syndrome: male w/o testes --> 46, XY female w/ both internal and external female genitalia


FSH, LH, E2 levels assc with 1/1 amenorrhea due to

central d/o
ovarian d/o
outflow tract obstruction

central d/o: low FSH/LH, low E2

ovarian d/o: high FSH/LH, low E2

outflow tract obstruction: normal FSH/LH, normal E2


1/1 amenorrhea management

1st: det if there is a uterus
- no uterus = MIF present = get karyotype to show 46, XY female

2nd: if there is a uterus, is there a vagina too?
- no vagina = outflow tract obst

3rd: are there breasts?
- breasts = E present = Progesterone challenge + (gets withdrawal bleeding)
- no breasts = E absent = Progesterone challenege negative (no withdrawal bleeding, bc the endometrium is not estrogenized)


what are the 4 types of etiologies for 2/2 amenorrhea?

pregnancy (MC)
acquired abnormalities
HPO axis disorder


What are aquired causes of 2/2 amenorrhea?

anatomic or ovarian abnormalities

- Asherman syndrome syndrome (intrauterine adhesions 2/2 to D&C, surgery, or endometritis)

- Cervical stenosis: surgical or obstetric trauma leading to scarring of cervical os

-PCOS: elevated LH, dec FSH, elevated E/T


why does hyperPRL lead to amenorrhea?

PRL inhibits GnRH (elevated TSH, dec DA, tumors)


decision tree for 2/2 amenorrhea?

1st: check b-hCG to r/o pregnancy

2nd check PRL
-elevated, get TSH
-normal give P challenge

elevated PRL and TSH = hyperthyroid causing amenorrhea

elevated PRL, nml TSH, abnormal cone view --> get CT/MRI head to determine if micro or macroadenoma (micro tx is bromocriptine; macro tx is surgery)

normal PRL with positive P challengre (gets withdrawal bleeding) --> hirsute = PCOS and non-hirsute = milkd hypothalamic dysfunction

normal PRL with negative P challenge test, 1st r/o asherman syndrome/cervical stenosis (= aquired obstructions) then get FSH.
-FSH > 40 = ovarian failure
-FSH < 40 = severe hypothalamic dysfucntion