Endo 9 - Endocrine Infertility

Question 1

Which cells within the testes does LH stimulate and what does it make these cells produce?

Answer 1

Leydig cells - Testosterone

Question 2

What is testosterone responsible for?

Answer 2

Secondary sexual characteristics and aids spermatogenesis

Question 3

Which cells within the testes does FSH stimulate and what does it make these cells produce?

Answer 3

Sertoli cells - stimulated to make sperm and inhibin A

Question 4

Where are the sertoli cells located>?

Answer 4

Seminiferous tubules

Question 5

What does inhibin A inhibit?

Answer 5

FSH secretion from the pituitary

Question 6

What are the 3 phases of the menstrual cycle?

Answer 6

Follicular phase, ovulation, luteal phase

Question 7

What does LH stimulate in the ovaries?

Answer 7

Oestradiol and progesterone

Question 8

What does FSH stimulate in the ovaries?

Answer 8

follicular development and inhibin production

Question 9

What effect does oestrogen have on the HPG axis in the follicular phase of the menstrual cycle?

Answer 9

Negative feedback - inhibits LH and FSH

Question 10

What does the leading follicle develop into by day 10?

Answer 10

Graffian Follicle

Question 11

Once oestrogen reaches a certain level is switches to positive feedback, how does it do this?

Answer 11

Increases GnRH secretion

Increases LH sensitivity to GnRH

Question 12

What does the mid cycle LH surge cause?

Answer 12

triggers ovulation

Question 13

Define infertility

Answer 13

inability to conceive after 1 year of regular unprotected sex

Question 14

What is primary gonadal failure and what effects does it have on the HPG axis?

Answer 14

Gonads not working
No production of oestrogen/testosterone so you will get

High GnRH, high FSH, high LH

Question 15

Describe the levels of hormones in the HPG axis in hypothalamic/pituitary disease?

Answer 15

Low FSH
Low LH
Low GnRH

Question 16

Clinical features of male hypogonadism?

Answer 16

loss of libido
impotence
small testes
decreased muscle bulk

Question 17

State 5 causes of male hypogonadism

Answer 17

Kallman's 
Hypopituitarism
Illness
Hyperprolactinaemia
Androgen receptor deficiency

Question 18

Name a congenital cause of primary hypogonadism

Answer 18

Klinefelters (XXY)

Question 19

Name an acquired cause of primary hypogonadism

Answer 19

Testicular torsion

Question 20

What are the main investigations for male hypogonadism?

Answer 20

Check hormones - LH, FSH, testosterone 
check MRI for pituitary if all low
Prolactin
Sperm count
Chromosomal analysis

Question 21

What hormone is given to all patients with hypogonadism?

Answer 21

Testosterone

Question 22

Why is testosterone given to all patients with hypogonadism?

Answer 22

to increase muscle bulk and protect against osteoporosis

Question 23

How do you restore fertility in someone with hypothalamic/pituitary disease?

Answer 23

Subcutaneous gonadotrophins

stimulates testosterone

Question 24

What is the treatment for hyperprolactinaemia?

Answer 24

Dopmaine agonists e.g. bromocriptine and cabergoline

Question 25

What are the main actions of testosterone?

Answer 25

- development of male genital tract - maintains fertility - secondary sexual characteristics - Anabolic e.g. muscle

Question 26

Is testosterone heavily protein bound or nah?

Answer 26

Heavily protein bound

Question 27

What two hormones can testosterone be converted to?

Answer 27

dihydrotestosterone (DHT) | 17-oestradiol

Question 28

What enzyme converts testosterone to DHT?

Answer 28

5- reductase

Question 29

Which enzyme converts testosterone to oestradiol?

Answer 29

Aromatase

Question 30

Which receptors does oestradiol work on?

Answer 30

oestrogen receptors

Question 31

What type of receptors are oestrogen receptors and androgen receptors?

Answer 31

Nuclear - have to go inside the nucleus to have their effect

Question 32

Does testosterone restore fertility?

Answer 32

No

Question 33

What is the difference between primary and secondary amenorrhoea?

Answer 33

``` primary = failure to develop spontaneous menstruation by age of 16 secondary = absence of menstruation for 3 months in a woman who previously had cycles ```

Question 34

What is oligomenorrhea?

Answer 34

irregularly long cycles

Question 35

List some causes of Ameorrhoea?

Answer 35

``` Pregnancy Lactation Ovarian failure Hypothalamic/Pituitary disease Kallman's Low BMI Obesity Post pill amenorrhoea ```

Question 36

State some of the features of Turner's syndrome

Answer 36

short stature | cubitus valgus

Question 37

State the investigations for amenorrhoea

Answer 37

``` Pregnancy test!!! LH, FSH, Oestradiol Prolactin Thyroid Chromosomal ```

Question 38

What two things is PCOS associated with?

Answer 38

increased cardiovascular risk | insulin resistance - diabetes

Question 39

What is the criteria for diagnosing PCOS?

Answer 39

Need 2 of the following - Polycystic ovaries - Clinical signs of androgen excess - Oligoovulation

Question 40

What are the clinical features of PCOS?

Answer 40

Hirsuitism Menstrual Irregularities Increased BMI

Question 41

What is the treatment of PCOS?

Answer 41

- control diabetes - metformin | - Clomifene - antioestrogenic in HPA so binds and stops negative feedback thus increases gonadotrophin release

Question 42

Which hypothalamic hormone has a stimulatory effect on prolactin?

Answer 42

thyrotrophin releasing hormone

Question 43

What effect does hyperprolactinaemia have on the HPG axis?

Answer 43

Reduces GnRH pulsatility | Switches off gonadal function

Question 44

State some causes of hyperprolactinaemia

Answer 44

Prolactinoma Dopamine Antagonists Pituitary adenoma PCOS

Question 45

What are the clinical features of hyperprolactinaemia?

Answer 45

Galactorrhoea hypogonadism prolactinoma - bitemporal hemianopia