Endocrine infertility Flashcards
What is infertility?
How often does it occur?
Inability to concieve after one year of regular unprotected sex
It occurs in 1:6 couples
Where are the causes for infertitlity?
Caused by abnormalities
- in males (30%)
- or females (45%)
- or unknown (25%)
—> Need to see whole couple for determining infertility
What are the clinical features of male hypogonadism?
All due to low Testosterone:
- loss of libido
- small testis
- loss of muscle bulk
- impotence
- osteoporosis
What are the causes for male hypogonadism?
- Hypothalamic/Pituitary reasons
- Hypopituitarism
- Kallmanns syndrome
- Illness/underweight (leptin effect on pituitary)
- Primary gonodal disease
- genetic (e.g. Kleinfeltery syndrome XXY)
- Aquired: testicular torison, Chemotherapy
- Hyperprolactinaemia
- Androgen receptor deficienyy
What is Kallmanns syndrome?
A syndrome that results in lowGnRH pressenting with
- loss of smell (anosmia)
- in males: no descend of testis + late puberty
Which investigatios would you perform when someone presents with symptoms of male hypogonadism?
Hormone levels
- LH, FSH high (lack of negative feedback)
- Testosterone low
Prolactin levesl
Sperm count
Chromosomal analysis (e.g. Kleinfelters XXY)
What is Azoospermia?
Absence of sperm in ejaculate
(How would you call)
Oligospermia
Reduced numbers of sperm in ejaculate
Absence of sperm in ejaculate
(How would you call)
What is Azoospermia?
What is
Reduced numbers of sperm in ejaculate
Oligospermia
How would you treat a male patient with Hypogonadism?
- Testosterone replacement for all patients
- When wish for fertility: also FSH + LH replacement required
- In Hyperprolactinaemia: Dopamine agonist
What are the possible sites for androgen production?
- Adrenals
- Testicles (Leydig cells)
- Ovaries
- placenta
- tumors
What are the main physiological actions of Testosterone?
- Development of male genitalia tract
- Maintains fertility in adulthood
- Control of 2nd sexual characteristics
- Anabolic effects: Muscle and Bone
Which pathways can testosterone undergo?
What are the enymes involved?
What are possible products?
Testosterone into
Dihydrotestosterone (via 5-alpha reductase) or
17ßEstradiol (Via Aromatase)
What are the effect of testosterone treatment in adulthood?
It will increase
- lean body mass
- muscle size and strength
- bone formation + bone mass (in young men)
- libido and potency (but for restoring fertility also LH + FSH are needed!)
What is oligomenorrhoea?
Prolonged, irregular periods
What are possible causes of Amenorrhoea?
- Pregnancy/ Lactation
- Ovarian failure
- premature ovarian failure
- Ovariectomy / chemotherapy
- ovarian dysgenesis (Turners 45 XO) – lacking one chromosome
- Gonadotrophin failure:
- Hypo / pit disease
- Kallmann’s syndrome (anosmia, Low GnRH)
- Low BMI (Leptin inhibition of GnRH release)
- Post pill amenorrhoea (exogenous hormone switches off hypothalamus)
- Hyperprolactinaemia
- Androgen excess: gonadal tumour
Which investigations would you perform on someone presenting with amenorrhoea?
- Pregnancy test
- Hormonal profile
- LH, FSH, oestradiol
- Day 21 progesterone
- Prolactin, thyroid function tests
- Androgens (testosterone, androstenedione, DHEAS)
- Chromosomal analysis (Turners 45 XO)
- Ultrasound scan ovaries / uterus
How would you treat somoen with amenorrhoea?
Treat the cause (eg low weight)!
Also treatment in dependant on the cause:
In Primary ovarian failure
- infertile, HRT
In Hypothalamic / pituitary disease
- HRT for oestrogen replacement
- If Fertility wanted: Gonadotrophins (LH & FSH) – part of IVF treatment
What is PCOS?
How often does it occur?
Polycystic ovarian syndrome
•Incidence: 1 in 12 women of reproductive age
How do you diagnose polycystic ovarian syndrome?
For a diagnosis: two of the following features are required:
- polycystic ovaries on USS
- oligo- / anovulation
- clinical / biochemical androgen excess
What is the relationship between PCOS and risk of CVS disease and diabetis
PCOS are associated with increased risk in diabetis and CVS disease
What are the clinical features of PCOS?
- Hirsuitism
- Menstrual cycle disturbance
- Increased BMI
How would you treat PCOS?
Metformin
- decreased testosterone production
Clomiphene
- Is anti-oestrogenic in the hypothalamo-pituitary axis
- –> blocks negative feedback thereby increaseing GnRH levels + levels of gonadotrophins
Gonadotrophin therapy as part of IVF treatment
What is Clomiphene?
What is it used for?
Is anti-oestrogenic in the hypothalamo-pituitary axis
–> blocks negative feedback thereby increaseing GnRH levels + levels of gonadotrophins
Explain the (off-label) use of Metformin in PCOS
It probably reduces androgen production
What are the causes for Hyperprolactinaemia?
- Dopamine antagonist drugs
- Anti-emetics (metoclopramide)
- Anti-psychotics (phenothiazines)
- Prolactinoma
- Stalk compression due to pituitary adenoma
- PCOS
- Hypothyroidism
- Oestrogens (OCP), pregnancy, lactation,
Idiopathic
Explain the role of the Thyroid in fertiltiy
Hypothyroidism might be a cause of infertility because
- Low T3/T4 –> no -ve feedback–>
- high TSH levels
- TSH has a stimmulating effect of prolactin release
- Prolactine has a inhibitory effect on GnRH and LH/FSH
What are the clinical features of somone with a hyperprolactinaemia?
Galactorrhoea
Reduced GnRH secretion / LH action >> hypogonadism
In a Prolactinoma:
- Headache
- Visual field defect
How would you treat someone with hyperprolactinaemia?
Treat the cause – stop drugs
Dopamine agonist
- Bromocriptine
- Cabergoline
Prolactinoma
- Dopamine agonist therapy (-ve feedback)
- Pituitary surgery rarely needed
Explain the production of female sex hormones and controll in the Hypothalamo/Pit Axis
What are the expected hormonal changes with PCOS?
- increase in androgens
- increase in LH
- (reduction in FSH)
