Lecture 5 - Endocrine Disorders Affecting Reproduction Flashcards
What is the pattern of release of GnRH and hence FSH and LH after puberty?
Released in a pulsatile fashion
What is the result of continual GnRH release?
It causes decreased FSH and LH release.
How is oestrogen produced in females?
Androgens are produced by the thecal cells in response to FSH and LH. These then move to the granulosa cells where they are converted to oestrodiol by aromatase.
What is oligomenhorrea?
Irregular periods so less than 9 periods a year
What is ammenhorrea and what are the types?
Stopping of periods.
Primary-failure of menarche after 16yrs
Secondary-no period for 6 months after menarche
What are the signs and symptoms of oestrogen deficiency?
Hot flushes, poor libido, dispareunia (painful sex)
What is the first test that must be done for amenorrhoea?
Pregnancy test
What are the three main causes of central amenorrhoea?
Hypothalamic - caused by weight loss, excercise, stress
Pituitary - lactation, pituitary tumours
Hypogonadotrophic hypogonadism - lack of FSH and LH secretion
What are the three ovarian causes of amenorrhoea?
Turners syndrome
Premature ovarian failure
Polycyctic ovary syndrome
What are the clinical features of hyperprolactinaemia in pre-menopausal women?
Hypogonadism which causes oligo/ammenorrhoea and symptoms of oestrogen deficiency
Galactorrhoea- producing milk when shouldn’t
What can cause pathological hyperprolacinaemia?
PRL-secreting pituitary tumours
Lack of negative feedback to pituitary from hypothalamus (pituitary stalk compression)
Dopamine antagonists as dopamine is the negative regulator.
What are the signs and symptoms of premature ovarian insufficiency?
Amenorrhorea
Oestrogen deficieny- signs and symptoms
Eleated FSH and LH
What are the causes of premature ovarian insufficiency?
Turners syndome
Autoimmune - thyroid, addisons
Iatrogenic - chemotherapy
Mutations in receptors e.g. FSH
What is fragile X and what does this lead to?
It is a genetic change linked to the FMR1 gene which can lead to premature ovarian insufficiency.
It has an X linked dominant pattern.
What are the signs and symptoms of Polycystic ovary syndrome?
Oligomenorrhea Hirtuism Obesity Infertility Polycyctic ovaries on ultrasound
What hormone levels are seen with polycycstic ovary syndrome?
Hyperandrogenism
Increased testosterone and DHEA
Increased LH/FSH ratio
Not deficient in oestrogens
Two out of three of which criteria must be present to diagnose PCOS?
Oligo/amenorrhoea
Polycystic ovaries
Hyperandrogenism
How is PCOS treated?
Try to get them to lose weight, metforin given to help control blood sugar.
Hirtuism can be treted with Yasmin or other creams
What are the main causes of androgen insensitivity syndrome?
Mutations in the androgen receptor resulting in the effects of the androgens not being transmitted to the cells.
What does 5 alpha reductase deficiency result in?
5 alpha reductase is needed for conversion of testosterone to the more potent dihydrotestosterone. This means that with a deficiency there can be ‘females’ with XY chromosomes that have not been able to convert the testosterone and hence do not have male secondary characteristics.
What are the results of male hypogonadism?
• Delayed puberty
• Psychological effects
– Loss of libido and reduced sexual behaviour
– Lack of sex drive versus erectile impotence
• Gynaecomastia
• Loss of body hair, reduced shaving frequency,
thin skin
• Decreased muscle mass, female fat distribution
• Osteoporosis
What are the two main types of the causes for hypogonadism?
Primary hypogonadism - problem in gonads e.g. surgery or chemo
Secondary hypogonadism - problem in pituitary e.g. tumour
What pattern of hormones suggest primary or secondary hypogonadism in males?
-High LH, FSH indicates primary gonadal failure
– Low LH, FSH suggests secondary cause
