Infertility Notes

Question 1

Describe the normal reproductive physiology e

Answer 1

GnRH pulses from the hypothalamus stimulate the release of LH and FSH from the pituitary gland > LH stimulated testerone production in the testes (leydig cells). Testosterone is responsible for secondary sexual characteristics and aids spermatogenesis. FSH stimulate Sertoli cells in semineferous tubules. Sperm and inhibin A and B. Negative feedback

Question 2

Describe the female reproductive physiology

Answer 2

1. Follicular phase: LH stimulates production of oestradiol and progesterone on ovaries > FSH stimulates follicular development and inhibin > by Day 10 the leading follicle turns to graffins follicular. Oestrogen initially negatively inhibits LH and FSH secretion, so in the follicular phase the HPG axis is the same as men.
2. Ovulation phase: once the oestrogen reaches a point, it switches from negative feedback to positive feedback, it increases GnRH release and increases LH sensitivity to GnRH which leads to mid cycle LH surge and triggers ovulation.
3. Luteal phase: if implementation does not occur = mensturation (endometrium shed), if implementation does occur = pregnancy.

Question 3

Define infertility and describe primary gonadal failure and hypothalamic failure

Answer 3

Infertility: inability to conceive after one year of regular unprotected sex

Primary gonadal failure: defects of the gonads - the testes or ovaries are not producing testosterone/ oestrogen so there is no negative feedback on the HOG axis means that you get high GnRH and high LH and FSH.

Hypothalamic failure: caused by inability of the pituitary gland to produce FSH and LH so their levels are low so less oestradiol/ testosterone so low FSH and LH

Question 4

Describe the effects of male hypogonadism (causes, symptoms, treatment and investigation)

Answer 4

Symptoms: loss of libido, impotence, small testes, decrease muscle bulk, osteoporosis

Causes: hypothalamic - pituitary diseases (hypopituitarism and kallmans), primary gonadal failure (kleinfelters and testicular torsion), hyperprolactinaemia (switches if GnRH)

Investigation: LH and FSH and Testosterone (if all low MRI pit), prolactin levels, sperm count, chromosomal investigation for kleinfelters.

Treatment: replacement testosterone, if hyperpituitarism - subcutaneous LH/FSH and if hyperprolactinaemia then dopamine agonist

Question 5

Disorders in female gonadism

Answer 5

Amenorrhea: absence of period, if primary = failure to begin, if secondary = then just randomly stopped. Causes: pregnancy, ovarian failure, ovarian dysgenia (turners XO) and lots of causes. Investigation: pregnancy test, Day 21 progesterone surge, chromosomal analysis. Treat with HRT and gonadotrophins

PCOS: polycystic ovaries in ultra sound, oligo/anovulation, clinical androgen test. Symptoms: hruitism, menstural cycle disturbance, increased BMI. Treatment: metformin, and clomiphene (fertility drug increases secretion of GnRH and gonadortiohin.

Hyperprolactinaemia: causes: prolactinoma, dopamine Antagonist medication, stalk compression, PCOS, hypothyroidism, oestrogen. Treatment: dopamine agonist: bronnocriptine, carbegoline, pit surgery.