Puberty and Growth Flashcards
WHO vs CDC growth curve
WHO
- Breastfed infants to 12m
- How kids should grow in ideal conditions
- No weight plot after age 10yrs – recommend plotting BMI only
- Addition of %iles – up to 99.9th and down to the 0.1th %iles
- International sample population (vs.US)
CDC
- Observational describe
how to measure growth proportions
1) U/L segment ratio
- lower segment = from the pubic symphysis to the ground while the child is standing straight with shoes off and feet
together
- upper segment= Subtract the lower segment from the total height
- Calculate ratio
**Normal is 1.7 in neonate to slightly below 1.0 in the adult.
2) Arm span
- Measure child’s arm span while she/he is standing with back touching wall and feet together. Arms should be fully extended against the wall and parallel to the floor with fingers together and outstretched, palms facing forward. Measure straight across (to length of 3rd finger), on the wall, once the child has stepped away.
**Should be ~ equal to height
3) Head circumference
- Measure from the occiput to the forehead around the head – objective is to measure maximal HC. Rpt 3x.
- Plot measurement on growth curve
Causes of abnormal proportions
Increased U/L
1. Achondroplasia
2. Hypochondroplasia
3. Turner
● Osteogenesis imperfecta
● Hypophosphatemic rickets
● (Pseudo)pseudohypoparathyroidism
Decreased U/L
1. Scoliosis
2. Spinal irradiation
where is GH produced/secreted
anterior pituitary somatotrophs
where is the Main organ GH acts to make IGF1
liver
GH receptor - what does it activate and cause
activates post receptor signaling through JAK/STAT
Leads to transcription of 3 important GH dependent genes:
IGF-1
IGFBP-3
ALS (acid labile subunit)
Growth hormone receptor pathway steps
- Dimerization of GH receptors
i. Different domains of a single GH molecule associate with homologous regions on 2 independent GH receptors, promoting dimerization of the receptors.
GH receptor lack a tyrosine kinase domain - Recruitment of JAK2 (Janus Kinase 2)
i. With dimerization, JAK2 is associated with and activated by the GH receptors. - Activation of JAK2’s intrinsic tyrosine kinase activity
i. JAK2 undergoes autophosphorylation and concurrently tyrosine phosphorylates the GH receptors - Recruitment of STAT (Signal Transducer & Activator of Transcription) Factors:
i. The phosphorylation of the GH receptors by JAK2, provides a docking station for STAT factors (STAT5a & STAT5b are most relevant to GH). - Transcription
i. STATs are phosphorylated. They dissociate from the GHR, migrate to the nucleus, and bind to specific STAT-binding DNA regulatory elements (SIE/ISRE/ GAS) responsible for transcriptional control of GH target genes such as IGF-1.
Pharmacologic agents that stimulate secretion of GH
- AMINO ACID
Arginine - NEUROTRANSMITTER
Clonidine (alpha adrenergic agonist)
L-dopa (dopamine agonist)
Propranolol (beta-adrenergic antagonist)
GABA agonists (muscimol)
ALPHA AGONIST
BETA ANTAGONIST
- HYPOGLYCEMIA
Glucagon (relative hypoglycemia)
Insulin (hypoglycemia) - HORMONES
GHRH
Peptide–ACTH, alpha-MSH, vasopressin
Estrogen - OTHER
Potassium infusion
Physiologic stimulants for GH
Hypoglycemia
Exercise
Sleep
Stress
Protein depletion/starvation/AN
Chronic renal failure
Ectopic production of GHRH
Acromegaly (TRH, GnRH)
physiologic inhibitors of GH secretion
Hyperglycemia (postprandial)
Elevated FFA
Obesity
Hypo or hyperthyroidism
Somatostatin
Progesterone
Glucocorticoids
Alpha adrenergic inhibition
Beta adrenergic stimulation (GH)
what hormones are involved in growth
Growth hormone
Thyroid hormone
Sex steroids
Corticosteroids
Growth hormone - other name
- stimulated by
- inhibited by
somatotropin
stimulated by GH-releasing hormone (GHRH or GRF)
suppressed by hypothalamic GH release-inhibiting factor (somatostatin or SRIF)
what does GH do directly, besides IGF1
stimulates lipolysis,
increased amino acid transport into tissues,
increased protein and glucose synthesis in liver
also has direct effect on cartilage growth
how is GH secreted throughout day
in a pulsatile manner
Clinical Signs of GH deficiency
- Poor growth
(increased fat mass leading to a chubby or cherubic appearance with immature facial appearance, immature high-pitched voice, and delay in skeletal maturation)
midface hypoplasia - Neonatal Hypoglycemia
- Prolonged jaundice
- Micropenis
- breech position
- delayed dentition
- giant cell hepatitis
- midline defects
- higher incidence of hyperlipidemia with elevated total cholesterol and low-density lipoprotein
what agent can be used for a GH stim test
L-Dopa
Clonidine
Arginine
Glucagon
Insulin-induced hypoglycemia (very dangerous)
GHRH
Growth hormone–releasing peptides (GRP)
how do corticosteroids affect growth
if XS - poor growth
if low, not a big effect if well otherwise
Acquired causes of GH deficiency
Hypothalamic-pituitary tumors
Histiocytosis X
Central nervous system infections
Head injuries
GH deficiency following cranial irradiation
Central nervous system vascular accidents
Hydrocephalus
Empty sella syndrome
Syndromes/Conditions w Short Stature + Obesity
Laurence-Moon
Biedl-Bardet
Prader-Willi syndrome
hypothyroidism,
glucocorticoid excess,
pseudohypoparathyroidism with Albright Hereditary Osteodystrophy
achondroplasia
gene
features
FGFR3 mutation
frontal bossing
mid-face hypoplasia
exaggerated lumbar lordosis
limited elbow extension
genu varum
trident hand
motor delay
spinal stenosis
obesity
intelligence normal
Russell silver syndrome
criteria for dx
4/6 of:
- SGA (birth weight and/or length ≥2 SD below the mean for gestational age)
- Postnatal growth failure (length/height ≥ 2 SD below the mean at 24 months)
- Relative macrocephaly at birth (HC >1.5 SD above birth weight and/or length)
- Frontal bossing or prominent forehead (forehead projecting beyond the facial plane on a side view as a toddler [1–3 years])
- Body asymmetry (limb length discrepancy ≥0.5 cm, or <0.5 cm with ≥2 other asymmetric body parts)
- Feeding difficulties or body mass index ≤2 SD at 24 months or current use of a feeding tube or cyproheptadine for appetite stimulation
what does SHOX stand for
Short stature HOmeoboX-containing gene
Noonan syndrome
short stature, webbed neck, low posterior hairline, and facial resemblance to Turner syndrome, but the karyotype is 46,XX in the female or 46,XY in the male
Prader Willi Syndrome
poor intrauterine movement,
acromicria (small hands and feet),
developmental delay
almond-shaped eyes along
infantile hypotonia
poor feeding as infant
short stature
insatiable hunger
obesity
glucose intolerance
delayed puberty
Prader Willi syndrome gene
lack of expression of paternally inherited imprinted genes on chromosome 15q11-13
when to stop GH therapy
GV <2cm/y
BA fused
GH Tx Side Effects
intracranial hypertension
slipped capital femoral epiphysis (SCFE)
scoliosis progression
Insulin resistance
Theoretical increased risk of malignancy
Gynecomastia (for boys)
Local reaction at site of injection
Increased growth of nevi (?)
Hypertrophy of tonsils/adenoids (?)
Laron syndrome
= GH insensitivity
Molecular mechanism:
- Primary GH resistance - Receptor mutation (decreased or absent).
Note: Decreased serum GHBP levels
- GH insensitivity - Post-receptor defects.
Note: Normal GHBP levels
- Primary IGF-1 deficiency – synthesis or receptor
Autosomal recessive
GH elevated due to decreased or absent IGF-1
Does not respond to GH treatment… need recombinant IGF-1
Causes of tall stature: nonendocrine
- constitutional tall stature
- genetic tall stature
- syndromes of tall stature
—Kilnefelter
—Marfan
—-Cerebral gigantism
—Homocystinura
—Beckwith-Wiedemann - XYY and XYYY syndromes
Causes of tall stature: endocrine
Pituitary gigantism
Sexual precocity
Thyrotoxicosis
IDM
GH excess - names
pituitary gigantism before epiphyseal fusion
acromegaly after
pituitary gigantism - features
Grow excessively rapidly,
coarse features,
large hands and feet with thick fingers and toes, and
often frontal bossing and large jaws
glucose intolerance or frank diabetes mellitus,
hypogonadism, and
thyromegaly
pituitary gigantism - causes
- GH secreting pituitary adenoma or somatotrophs
- constitutive activation of GH secretion as is sometimes found in the McCune-Albright syndrome
- excess secretion of GHRH
ectopic GH secretion (rare)
thyrotoxicosis and growth
increased growth, advanced bone age, and, if occurring in early life, craniosynostosis
how to test for pituitary gigantism
GH suppression test with OGTT
1.75g/kg oral glucose (max 75g)
measure serum GH before and two hours after glucose administration
GH should be <1 or 5 ng/L depending on resource
effects of anorexia nervosa
- GH axis: low IGF1, normal or high GH
- insulin: low
- cortisol: high
- thyroid: sick euthyroid
- hypogonadotropic hypogonadism
- decreased leptin and oxytocin
- increase ghrelin, peptide YY and adiponectin
Signs of estrogenization
- Breast development (mainly from E, but other factors too)
- Areolae become more pigmented and erectile as development progresses
- Enlargement of the labia minora and majora
- Dulling of the vaginal mucosa from its prepubertal reddish hue to pink (due to cornification of the vaginal epithelium),
- Production of a clear or slightly whitish vaginal secretion prior to menarche
Start of central puberty in males
- physiology
Starts with testicular enlargement
2.5cm or 4ml
Most of the increase in testicular size is due to seminiferous tubular development secondary to stimulation by follicle-stimulating hormone (FSH), with a smaller component due to Leydig cell stimulation by luteinizing hormone (LH)
hCG secreting tumour - what happens to male testes
Leydig cells are stimulated by LH (not FSH) so the testis does not grow as large as in normal puberty. (but they do enlarge)
mechanism of earlier puberty in obese females
local aromatase activity in adipose tissue
how does estrogen affect growth
- indirectly stimulates IGF-I production by increasing the secretion of GH
- directly stimulates IGF-I production in cartilage
- stimulating maturation of the chondrocytes and osteoblasts, ultimately leading to epiphysial fusion
when do boys and girls reach peak mineralization of bone
Girls reach peak mineralization between 14 and 16 years of age, whereas boys reach a later peak at 17.5 years
female athletic triad
exercise-induced amenorrhea,
premature osteoporosis, and
disordered eating
sex hormone binding protein - factors that increase and decrease
Factors that increase
Estrogen (& Tamoxifen) / Pregnancy
Thyroid hormone administration & hyperthyroidism
Phenytoin
Cirrhosis
HIV?
Factors that decrease
Hypothyroidism
Nephrotic syndrome
GH administration / Acromegaly
Obesity & hyperinsulinemic states
Exogenous androgens
Glucocorticoids
during fetal life, what hormones are produced by the male and female gonads
Males:
- LH stimulates the Leydig cells to secrete testosterone, and
- FSH stimulates the Sertoli cells to produce inhibin. Inhibin feeds back on the hypothalamic-pituitary axis to inhibit FSH
Females:
- FSH stimulates the granulosa cells to produce estrogen and the follicles to secrete inhibin
what is another important hormone for pubertal development
Leptin is a necessary component of pubertal development in human beings but not a major stimulant to this development; leptin is necessary but not sufficient for pubertal development.
what hormones play roles of importance in the onset of puberty?
kisspeptin (KISS1)
GRP54 (kisspepin receptor, G protein–coupled receptor 54)
MKRN3 (precocious puberty)
DLK1 (precocious puberty)
LEP
LEPR
TAC3
TAC3 receptor
when do the adrenal glands start secreting androgens
The adrenal cortex normally secretes the weak androgens dehydroepiandrosterone (DHEA), its sulfate, dehydroepiandrosterone sulfate (DHEAS), and androstenedione in increasing amounts beginning at about 6 to 7 years of age in girls and 7 to 8 years of age in boys
what are metabolic changes during puberty
boys:
hematocrit rises
high-density lipoprotein (HDL) concentrations fall
both boys and girls
alkaline phosphatase rises normally during the pubertal growth spurt
Serum IGF-I concentrations rise with the pubertal growth spurt, but IGF-I is more closely correlated with sex steroid concentration than with growth rate
when do IGF1 levels peak
1 year after peak growth velocity is reached and remain elevated for 4 years thereafter, even though growth rate is decreasing
classification of causes of delayed puberty
Constitutional delay in growth and adolescence
Hypogonadotropic hypogonadism
Hypergonadotropic hypogonadism
Causes of central delayed puberty
Constitutional delay in growth and adolescence
Central nervous system disorders
- Congenital disorders of the hypothalamus or pituitary
- Tumors
- Other acquired disorders
- Infection
- Trauma
- Irradiation
Defects of the hypothalamic-pituitary axis
- Isolated gonadotropin deficiency
—Kallmann syndrome
—Gonadotropin deficiency with normal sense of smell (Idiopathic Hypogonadotropic Hypogonadism)
- Multiple pituitary hormonal deficiencies
- Miscellaneous disorders
—Syndromes
—Chronic disease
—Weight loss
—Anorexia nervosa
—Increased physical activity in female athletes
—Hypothyroidism
Genetic syndromes
- Prader-Willi syndrome
- Bardet-Biedl syndrome
Causes of Hypergonadotropic hypogonadism
Male phenotype
- Klinefelter syndrome (gonadal dysgenesis)
- Other forms of primary testicular failure (including chemotherapy, autoimmune, radiation, trauma)
- Enzymatic defects of androgen production
- Anorchia or cryptorchism
Female phenotype
- Turner syndrome(gonadal dysgenesis)
- Other forms of primary ovarian failure (including chemotherapy)
Pseudo–Turner syndrome
Noonan syndrome
XX and XY gonadal dysgenesis
Klinefelter (47,XXY karyotype)
Hypergonadotropic Hypogonadism
primary testicular failure – seminiferous tubule dysgenesis
decreased upper segment-lower segment ratios
small testes
developmental delay
personality disorder
what happens in Klinefelter syndrome to testes
Onset of puberty is not usually delayed, because Leydig cell function is characteristically less affected than seminiferous tubule function in this condition and testosterone is adequate to stimulate pubertal development.
Serum gonadotropin levels rise to castrate concentrations after the onset of puberty; the testes become firm and are rarely larger than 3.5 cm in diameter
After the onset of puberty, there are histologic changes of seminiferous tubule hyalinization and fibrosis, adenomatous changes of the Leydig cells, and impaired spermatogenesis
Vanishing Testes Syndrome
46,XY
otherwise normal a
late fetal loss of the testes
normal infantile male genital development, including Wolffian duct formation and Müllerian duct regression.
The testes were presumably present in these patients early in fetal life during sexual differentiation, but degenerated after the 13th week of gestation for unknown reasons
isosexual precocity vs contrasexual precocity
isosexual precocity: feminization in girls and virilization in boys
contrasexual precocity: feminization in boys and virilization in girls
Causes of Central precocious puberty
- Constitutional
- Idiopathic
- Central nervous system disorders (including congenital defects)
—Tumors (Hypothalamic hamartoma, astrocytoma, glioma)
—Infection
—Trauma
—Radiation
—CNS disorders (static encephalopathy, low dose cranial irradiation, hydrocephalus)
—Following androgen exposure
-Profound hypothyroidism
Causes of Peripheral precocious puberty
Males
Gonadotropin-secreting tumors
Excessive androgen production
Testicular or adrenal tumors
Virilizing congenital adrenal hyperplasia
Premature Leydig and germinal cell maturation
hCG secreting tumours
Females
Ovarian follicular cysts
Estrogen-secreting neoplasms
Severe hypothyroidism
Granulosa cell tumour
Males and females
McCune-Albright syndrome
Exogenous exposure
treatment for PCOS
Lifestyle – weight loss is 1st line therapy in overweight/obese subjects
OCPs:
Raise SHBG -> decrease testosterone effects;
may decrease ovarian hyperandrogenism;
induces regular menses
Metformin:
induces regular menses;
short term improvement of metabolic derangements in obese subjects
Anti-Androgen:
spironolactone – as adjuvant with OCPs and metformin
What is def of ISS
○ height standard deviation score (SDS) ≤ –2.25 (PES)
○ unlikely to permit attainment of adult height in the expected range
indications for GH treatment
GH deficiency
Turner syndrome
ISS
SGA with no catch up growth by age 3 yo
SHOX haploinsufficiency
CKD
Prader-Willi
factors that alter IGF1
● GH deficiency
● GH resistance
● Malnutrition
● Hepatic failure
● Age (low in newborns, increases throughout childhood, peaks during puberty)
● Pubertal status
● Chronic disease and infections
● Pregnancy
● Thyroid function
syndromes associated with SHOX deficiency
i) Leri-Weill dyschondrosteosis (heterozygous defect)
ii) Langer mesomelic dysplasia (homozygous defect)
iii) Turner Syndrome
features associated with SHOX deficiency
i) Mesomelia - shorter forearms and lower legs (with reductions in arm span and leg length compared with trunk)
ii) Madelung deformity of the forearm (focal dysplasia of the distal radial physis)
iii) Short 4th or 5th metacarpal or metatarsal
iv) cubitus valgus (increased carrying angle of the arm)
v) high-arched palate
vi) scoliosis
vii) micrognathia
viii) muscular hypertrophy (reflected as a short, stocky appearance)
when can you dx GHD without stim
1) Patients has all 3 of the following: auxological criteria, hypothalamic-pituitary defect, and deficiency of at least one additional pituitary hormone
2) Newborn with hypoglycemia who does not attain a serum GH concentration above 5 μg/L and has deficiency of at least one additional pituitary hormone and/ or the classical imaging triad (ectopic posterior pituitary and pituitary hypoplasia with abnormal stalk)
starting dose of GH
○ Starting dose should be 0.16-0.24 mg/kg/week
what to monitor during GH treatment
IGF-1 should be maintained in normal range throughout growth hormone therapy
growth
if retesting for GHD as an adult, how long do you have to wait to be off GH?
1 month
what growth velocity change is consistent with GH deficiency
- Height velocity below -2SD over 1 year
- Height velocity more than 1.5SD below mean sustained over 2 years
side effects of clonidine
● Hypotension
● Drowsiness
● Dizziness
● Dry eyes or mouth
● Blurry vision
side effects of arginine
● flushing
● nausea and vomiting
● hypoglycemia
what is the expected growth of someone w ISS taking GH
For those with ISS they can expect a 5 cm height gain over 5 years of treatment
Dasatinib
tyrosine kinase inhibitor
needed for life in CML patients
This can sometimes affect growth hormone tyrosine kinase receptor and IGF-1 signalling pathway as well as chondrocyte action at the growth plate. Due to this many patients have short stature, although most have catch up growth once they hit puberty.
how does arginine affect GH
Arginine inhibits somatostatin
how do alpha adrenergic affect GH
Alpha adrenergic agonists (clonidine), dopamine (levodopa), and exercise cause release of GHRH
short and relative macrocephaly? think
Russell Silver syndrome
if someone starts GH treatment for GHD then has hypoglycemia, what is going on and what is the mechanism
Adrenal insufficiency
Inhibition of 11β-hydroxysteroid dehydrogenase 1
- 11B HSD1 catalyzes cortisone → cortisol in adipose tissue and liver and 11B HSD2 cortisol → cortisone in kidney. Evidence that GH indirectly (through IGF-1) modulates cortisol metabolism by decreasing 11B HSD1 activity (ie you have less cortisone → cortisol conversion), which if there is some semblance of decreased cortisol production, can lead to AI once you give GH
how does malnutrition affect growth
Malnutrition usually causes a drop in IGF-1. This occurs by decreasing availability of the GH receptor on the liver. Therefore malnourished patients do not respond to GH.
primary amenorrhea defintion
no period by age 16 yo
secondary amenorrhea definition
no menses for more than 3 cycles or more in someone who previously had cyclic menses
secondary amenorrhea causes
tumour(cranio)
1. Pituitary adenoma
2. Kallmann syndrome
3. Malnutrition
4. Anorexia/extreme weight loss
5. Sheehan syndrome
6. Trauma
7. TB
8. Meningitis/Encephalitis
9. History of radiation
10. LCH
11. Sarcoidosis
defects in estrogen biosynthesis
● 17,20-lyase deficiency
● CYP17a deficiency
● StAR mutation
pubertal gynecomastia pathophys
A transient increase in the estradiol to testosterone ratio
concerning features on exam for a male with gynecomastia
i) Tall stature (and/or developmental delay)
ii) Stigmata of liver disease (spider angiomas, jaundice, scleral icterus, etc)
iii) Abdominal mass
iv) Testicular mass
v) Gynecomastia greater than 4 cm in size
vi) Undervirilized male genitalia
vii) Small firm testes
■ Early accelerated linear growth (aromatase excess)
■ Signs of renal disease
concerning features on history for a male with gynecomastia
i) Galactorrhea (more likely prolactinoma, etc)
ii) Readily increasing gynecomastia
iii) Lack of pubertal progression
iv) Exogenous estrogen exposure
v) History of testicular trauma/injury or pituitary trauma or injury
vi) Symptoms of other pituitary deficiencies
vii) History of cryptorchidism
viii) Duration longer than 2 years
ix) Breast cancer findings
Endocrinopathies with McCune Albright
Cushing syndrome,
hyperthyroidism,
growth hormone excess,
hyperpararthyroidism
what are estrogen secreting tumours
ovarian, Sertoli cell, adrenal tumours
gonadal dysgenesis
- presentation
- labs
- karyotype
some estrogen effects (breast devel)
amenorrhea
○ Elevated FSH/LH
○ Low estradiol
○ Deletion of Xp only or iso-Xq (deletion of Xp causing fusion of 2 Xqs)
what happens to AMH during puberty
low
pituitary causes of secondary amenorrhea (6)
○ Pituitary tumor
○ Hyperprolactinemia
○ Surgery or radiation
○ Autoimmune
○ Infections
○ Hypotensive event (Sheehan syndrome)
Ddx for primary amenorrhea with breast development
○ Functional hypogonadotropic hypogonadism (low weight, low estradiol)
○ Turner syndrome (Webbed neck, high FSH)
○ Noonan’s (murmur, low LH on stim)
○ Prader Willi or Bardet Beidl (obesity, low LH on stim)
○ XX and XY gonadal dysgenesis (virilized genitalia, Y chromosome material on FISH)
○ Primary gonadal failure (post-radiation, etc) (normal external genitalia/vaginal atrophy/lack of pubertal development, high FSH)
○ CHH (incomplete or no breast development, LH low on stim)
○ Multiple pituitary hormone deficiencies (midline defect, low LH on stimulation testing)
○ Intact hymen (hematocolpos, normal estradiol)
○ Complete AIS (no virilizing features, Y chromosome on karyotype)
○ PCOS (androgenizing features, elevated testosterone)
○ NCCAH (androgenizing features, elevated 17-OHP)
2 meds to treat gynecomastia
aromatase inhibitor (anastrazole)
selective estrogen receptor blocker (tamoxifen)
meds that cause gynecomastia
■ Drugs
Marijuana use
Spironolactone
Estrogen
■ Hyperprolactinemia
■ Hypogonadism
■ Hyperthyroidism
■ AIS (partial)
■ Excessive aromatase activity
■ Liver disease
■ Uremia
■ Testicular germ cell or Leydig cell tumors
■ Feminizing adrenocortical adenoma or carcinoma
■ hCG-secreting nontrophoblastic neoplasm
med associated w gynecomastia
○ Spironolactone
○ Cimetidine
○ Ketoconazole
○ Estrogens
○ Anti-androgens
○ Growth hormone
○ GnRH analogue
○ 5 alpha reductase inhibitors
○ Marijuana
○ TCA
○ Ethanol
○ Heroin
○ Amphetamines
○ Anabolic steroids
what raises and lowers SHBP
factors that increase SHBG
-Drugs: tamoxifen/anti-epileptic drugs
-Untreated hyperthyroidism
-Estrogen
-Pregnancy
factors that decrease SHBG
-Exogenous androgens
-Glucocorticoid therapy
-GH treatment
-Untreated hypothyroidism
-Obesity
-Hyperinsulinemic states
how does T work at receptor
- T or DHT binds to androgen receptor
- Androgen/androgen receptor complex dissociates from Heat Shock Proteins and chaperone proteins, leading to a conformational change
- Conformational change leads to formation of a homodimer with another androgen/androgen receptor molecule
- Homodimer translocated to nucleus via binding to transport proteins, importins
- Now in the nucleus, androgen/androgen receptor molecule binds to androgen response elements in DNA and interacts with protein coactivators
- Initiates transcriptional activity
initial effects of GnRH agonist
■ Withdrawal bleed
■ Catch down growth (GV decreases within 5 months after the start of therapy)
side effects of GnRH agonist
■ Sterile abscesses
■ Decrease BMD
GnRH stim - what if LH or FSH predominates
a) LH predominance
-pubertal (central puberty) that you should treat
b) FSH predominance
-slow/intermittently progressing central precocious puberty
how does cranial irradiation affect puberty?
At medium dose cranial radiation there is a chance of developing precocious puberty (central), however at a high dose individuals can develop LH and FSH deficiencies
in premature ovarian failure, what is the most common etiology
Ovarian failure due to follicle depletion
how to assess fertility in females
AMH is representative of ovarian reserve.
However inhibin B is present during the follicular phase if there is a dominant follicle.
Therefore AMH s reflective of future fertility, but inhibin B and FSH are representative of current fertility ability.
