Spermatogenesis and male infertility Flashcards
What determines gender
chromosomal sex
gonadal sex
genital sex
gender
What is androgen insensitivity syndrome
Congenital condition where the body does not respond to androgens/testosterone
AMH is still produced causing formation of testes but lack of response to testosterone means that female external genitalia form even though chromosomes are 46XY
What controls testes descent
Androgen dependant
What is cryptorchidism
undescended testes
What are the contents of the spermatic cord
3 arteries: testicular, deferential, cremasteric
3 nerves: genitofemoral, cremasteric, sympathetics
3 fascia: internal + external spermatic fascia, cremasteric fascia
3 others: vas deferens, pampiniform plexus, lymphatics
What are the roles of the Sertoli cells
Maintain blood testes barrier Provide nutrients Phagocytosis Secretion of inhibin (inhibits FSH) and activin (stimulates FSH) Secrete androgen binding globulin ABG Secrete seminiferous tubule fluid
What happens to sperm after ejaculation
It is liquified by enzymes from the prostate gland
What are the roles of the seminal glands
secretes: fructose flavins semen prostaglandins fibrinogen
What does the prostate gland secrete
alkaline fluid - to neutralise the vaginal acidic pH
clotting enzymes
What happens to erectile tissue during an erection and what is the nerve supply
Erectile tissue engorges with blood - corpus cavernosum
parasympathetic - point
What is the nerve supply in ejaculation
Sympathetic - shoot
definition of male infertility
infertility from failure of sperm to normally fertilise the egg
what are causes for male infertility
obstructive
non-obstructive
idiopathic
List obstructive causes for male infertility
CF - congenital absence of vas deferens
infection
vasectomy
List non-obstructive causes for male infertility
cryptorchidism iatrogenic - radio/chemotherapy malignancy genetic - Klinefelters infection - mumps globozoospermia - no acrosome in sperm endocrine: hypothalamic - Kallmans, anorexia, tumour, infection pituitary - PRLoma, acromegaly, Cushing's thyroid DM Congenital adrenal hyperplasia androgen insensitivity ANABOLIC steroids
What should be covered in male infertility history taking
previous successful pregnancies facial hair tiredness libido loss of early morning erection? - definite decrease in testosterone
What should be covered in male infertility examination
General: 2ndary sexual characteristics, gynaecomastia
Genital: testicular volume, vas deferens palpable, penis, varicocele, hernias, lumps
What is the normal testicular volume
15-25 ml
What is looked for in semen analysis
Minimum limits: volume - 1.5ml density - 15 million/ml progressive motility 32 morphology 4%
How long should men be abstinent when giving a semen sample
2-7 days
Sample must be delivered within 1 hour
what further assessments can be done
repeat semen analysis 6 weeks later
hormone levels - FSH, LH, testosterone, PRL, TSH
chromosomal analysis - karyotype, CF screen
biopsy, scrotal scan
What would the results be in obstructive male infertility
normal 2ndary sexual characteristics
normal testicular volume
+- vas deferens
normal hormone levels
What would the results be in non-obstructive male infertility
poor 2ndary sexual characteristics
reduced testicular volume
vas deferens present
abnormal hormone levels
at what gestational week can you differentiate external genitalia on USS
16 weeks
