Spermatogenesis and male infertility

Question 1

What determines gender

Answer 1

chromosomal sex
gonadal sex
genital sex
gender

Question 2

What is androgen insensitivity syndrome

Answer 2

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

Question 3

What controls testes descent

Answer 3

Androgen dependant

Question 4

What is cryptorchidism

Answer 4

undescended testes

Question 5

What are the contents of the spermatic cord

Answer 5

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

Question 6

What are the roles of the Sertoli cells

Answer 6

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

Question 7

What happens to sperm after ejaculation

Answer 7

It is liquified by enzymes from the prostate gland

Question 8

What are the roles of the seminal glands

Answer 8

secretes: 
fructose 
flavins 
semen 
prostaglandins 
fibrinogen

Question 9

What does the prostate gland secrete

Answer 9

alkaline fluid - to neutralise the vaginal acidic pH

clotting enzymes

Question 10

What happens to erectile tissue during an erection and what is the nerve supply

Answer 10

Erectile tissue engorges with blood - corpus cavernosum

parasympathetic - point

Question 11

What is the nerve supply in ejaculation

Answer 11

Sympathetic - shoot

Question 12

definition of male infertility

Answer 12

infertility from failure of sperm to normally fertilise the egg

Question 13

what are causes for male infertility

Answer 13

obstructive
non-obstructive
idiopathic

Question 14

List obstructive causes for male infertility

Answer 14

CF - congenital absence of vas deferens
infection
vasectomy

Question 15

List non-obstructive causes for male infertility

Answer 15

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

Question 16

What should be covered in male infertility history taking

Answer 16

previous successful pregnancies 
facial hair 
tiredness 
libido 
loss of early morning erection? - definite decrease in testosterone

Question 17

What should be covered in male infertility examination

Answer 17

General: 2ndary sexual characteristics, gynaecomastia
Genital: testicular volume, vas deferens palpable, penis, varicocele, hernias, lumps

Question 18

What is the normal testicular volume

Answer 18

15-25 ml

Question 19

What is looked for in semen analysis

Answer 19

Minimum limits: 
volume - 1.5ml 
density - 15 million/ml
progressive motility 32
morphology 4%

Question 20

How long should men be abstinent when giving a semen sample

Answer 20

2-7 days

Sample must be delivered within 1 hour

Question 21

what further assessments can be done

Answer 21

repeat semen analysis 6 weeks later
hormone levels - FSH, LH, testosterone, PRL, TSH
chromosomal analysis - karyotype, CF screen
biopsy, scrotal scan

Question 22

What would the results be in obstructive male infertility

Answer 22

normal 2ndary sexual characteristics
normal testicular volume
+- vas deferens
normal hormone levels

Question 23

What would the results be in non-obstructive male infertility

Answer 23

poor 2ndary sexual characteristics
reduced testicular volume
vas deferens present
abnormal hormone levels

Question 24

at what gestational week can you differentiate external genitalia on USS

Answer 24

16 weeks