adolescent gynae Flashcards
what is the average age of puberty in
a) girls
b) boys
a) girls 10.5 years (secondary sex characteristics range from 9-13 years)
b) boys 11.5 years
what do the following terms mean:
Consonant puberty
Disconsonant puberty
Isosexual
contrasexual
constant: follows normal sequence of pubertal development (i.e. tanner stages)
Disconsonant puberty: abnormal sequence of pubertal changes
Isosexual - secondary sex characteristics match karoytpe
contrasexual - secondary sex characteristics opposite to karotype.
at onset of puberty what happens to GnRH release
changes from continuous to pulsatile release at night
what hormone does the pulsatile GnRH release trigger and is vital for the start of puberty?
LH
pre-pubertal what is the FSH: LH ratio
FSH>LH
pubertal what is the FSH: LH ratio
LH> FSH
what age defines precocious puberty in
a) girls
b) boys
a) girls < 8 years
b) boys <9 years
what is the first pubertal sign in females
a) Menarche
B) thelarche
c) pubarche
d) adrenarche
b - thelarche (avg age 9-13 years, commonly age 10)
what is the name of the staging system used in pubertal development
tanner stages (5 stages); stage 1 pre-pubertal stage
what happens in adrenarche?
adrenal glands produce androgens which are converted by the liver and ovaries to oestrogen. Responsible for:
- pubic hair growth
-acne/ oily skin
-body odour
-sweating
what is the second sign of pubertal development in girls
a) Menarche
B) thelarche
c) pubarche
d) adrenarche
c) pubarche (pubic hair growth)
what is the third and final stage of pubertal development in girls?
a) Menarche
B) thelarche
c) pubarche
d) adrenarche
a) menarche (avg age 12.8 years)
what is the average age of menarche?
12.8 years
what age would you classify primary amenorrhoea with no secondary sex characteristics
age 13
what age would you classify primary amenorrhoea when secondary sex characteristics are present
age 15
what tanner stage does menarche coincide with
tanner stage 3 (only 5cm of growth left at onset of menarche)
what gonadotrophins are responsible for male puberty and development of male secondary sex characteristics
testosterone and DHT (metabolite of T)
what is the average age of spermarchy in boys and what tanner stage does this correspond to?
13.4 years - tanner stage 3 -4
how can we categorise causes of precocious puberty
central (gonadotrophin hpg axis dependent) or peripheral
what is the usual order of male pubertal development
testicular enlargement
scrotum thickens and develops
spermarche - avg age 13.4 years
growth spurt –> GH driven
what are the two physiological processes that must take place in order for pubertal development
- adrenarche = increased production of androgens by adrenal cortex –> responsible for pubic hair, oily skin, acne, body odour, sweating etc (this can happen age 6-8 years in girls!)
- gonardarche - activation of gonads due to pulsatile release of GnRH – triggers LH release
When is precocious puberty more of a worrying sign - in females or males?
males worrying feature,
usually benign in females
can you name some of the causes of central precocious puberty
80% females and 40% males no cause is found
HPG dependent cause
- CNS lesions - tumours( gliomas/ hcg secreting tumours) , hypothalamic harmatoma
- CNS trauma
- iatrogenic - radiotherapy to CNS
- infective - meningitis/ encephalitis
-congenital CNS lesions e.g. hydrocephalus, arachnoid cysts
central precocious puberty what is the gold standard diagnostic test:
- ACTH suppression test
- early morning cortisol
- FSH and LH
- GnRH stimulation test
- MRI/CT head
- estradiol
- GnRH stimulation test
note - estradiol levels not reliable
If diagnosing central precocious puberty which of the following results would confirm the diagnosis: (SBA)
- GnRH stimulation test - no response, LH and FSH low
- GnRH stimulation test - LH and FSH very high, FSH > LH
- GnRH stimulation test - LH and FSH very high, LH > FSH, ratio > 8
- GnRH stimulation test - LH and FSH very high, LH > FSH, ratio > 5
- GnRH stimulation test - LH and FS very high i.e. good response, LH> FSH ratio > 8
what effect does raised prolactin e.g. due to a pituitary adenoma would you expect to see in terms of pubertal development
prolactinaemia usually causes delayed puberty rather than precocious
what is the main medical treatment method of central precocious puberty
a) HRT
b) estrogen
c) GnRH analogues
d) hydrocortisone
Treat the underlying cause e.g. surgery
c) GnRH analogues (agonist) e.g. leuprorelin, goserelin - these suppress the hpg axis
aim is to halt/ regress progress of secondary sex characteristics,
prevent early menarche
postpone bone maturation and improve final height
the earlier you start the GnRH analogue the better the outcome of improving final height (, 6 years old)
what effect do GnRH analogues when used in the treatment of central precocious puberty have on BMD in children
no effect
how can you monitor the effect of GnRH analogues when used in the treatment of central precocious puberty
GnRH stimulation test –> LH suppression indicates effective treatment