T2 L20 Physiology of puberty

Question 1

what is the definition of puberty?

Answer 1

Stage of physical maturation where an individual becomes physiologically capable of pro-creation

Question 2

What are the 3 general physical changes that occur during puberty?

Answer 2

Growth spurt
Secondary sex characteristics
Menarche / spermatogenesis

Question 3

What are the 5 physical changes occurring during puberty for girls?

Answer 3

Growth spurt
Breast growth
Pubic hair
Axillary hair
Menstruation

Question 4

When do girls experience a growth spurt?

Answer 4

8-14 years
6-10cm per year
2.5 year duration

Question 5

When does thelarche occur?

Answer 5

8-13 years

Question 6

When does pubic hair growth occur in girls?

Answer 6

9-13 years

Question 7

When does menarche occur?

Answer 7

10-16 years

Question 8

When does pulsatile nocturnal GnRH release start?

Answer 8

At 6-9 years

Occurs every 90-120 minutes

Question 9

Describe the endocrine changes during puberty

Answer 9

Increased GnRH leads to increased FSH and LH
Ovaries / testes become sensitised to effects of FSH and LH
Final phase is development of positive / negative feedback mechanism

Question 10

What can be used to check the adrenals are stimulated?

Answer 10

Urine steroid profile

Question 11

What do the testes produce?

Answer 11

Games (sperm)

Androgens (testosterone)

Question 12

What controls Sertoli cells?

Answer 12

FSH

Question 13

What controls leydig cells?

Answer 13

LH

Question 14

What produces androgens?

Answer 14

95% from testes

5% from adrenals

Question 15

What are the 2 phases in the ovarian cycle?

Answer 15

Follicular phase

Luteal phase

Question 16

What happens in the follicular phase of the ovarian cycle?

Answer 16

Initially E rises (FSH) with LH surge mid-cycle

Ovulation occurs

Question 17

What happens in the luteal phase of the ovarian cycle?

Answer 17

Negative feedback after ovulation

No further ovulation in same cycle

Question 18

What is the age of menarche related to?

Answer 18

General health
Genetic factors
Nutritional factors

Question 19

What was the mean age of menarche in 1840?

Answer 19

16.5 years

Question 20

What was the mean age of menarche in 1990?

Answer 20

12.8 years

Question 21

Describe the link between body weight/fat and menarche

Answer 21

Mean weight at menarche is 47.8kg
16-24% of body weight is fat
Athletes and patients with anorexia often have a late onset

Question 22

When does adrenarche occur in girls?

Answer 22

Starts at 6

Adequate levels by 8

Question 23

When does adrenarche occur in boys?

Answer 23

Starts at 8

Adequate levels by 10

Question 24

What is the chronological order of puberty in girls?

Answer 24

Growth spurt
Breast development
Pubic hair
Axillary hair
Menarche

Question 25

What is the chronological order of puberty in boys?

Answer 25

Testicular volume 
Penile length
Pubic hair
Growth spurt
Axillary / facial hair
Deep voice

Question 26

When is puberty considered early or precocious?

Answer 26

Below 8 years in girls

Below 9 years in boys

Question 27

What is early or precocious puberty?

Answer 27

Presence of true pubertal features at young and inappropriate age

Question 28

What is central or true precocious puberty dependent on?

Answer 28

Gonadotrophin dependent

Question 29

What are the concerns in early or precocious puberty?

Answer 29

Possible underlying sinister cause
Emotional or psycho-social upheaval at inappropriately young age
Early cessation of growth leading to decreased final adult height

Question 30

When is puberty considered to be delayed?

Answer 30

Above 14 years for girls or boys

Question 31

What is delayed puberty?

Answer 31

Absence of true pubertal onset at an appropriate age

It isn’t necessarily a lack of periods

Question 32

What are the concerns with delayed puberty?

Answer 32

Possible sinister underlying cause
Fear that puberty will never occur
Emotional and psychosocial upset of immaturity
Long term sequelae of reduced bone mineralisation

Question 33

What is a hypothalamic hamartoma?

Answer 33

Non-neoplastic homogenous sessile mass

Iso-intense to brain parenchyma in region of tuber cinerium in hypothalamus

Question 34

What is the treatment of central precocious puberty?

Answer 34

Long-acting LHRH analog therapy
- sustained supra-physiological LHRH levels
-paradoxical cessation of gonadotrophin release
-stops further pubertal progression
Pubertal progression will resumed when treatment is stopped at 10-12 years

Question 35

How common is Klinefelter syndrome?

Answer 35

1 in 1000 male infants

Question 36

What are the symptoms of Klinefelter syndrome?

Answer 36

Frontal baldness absent
Poor beard growth
Tendency to grow fewer chest hairs
Narrow shoulders
Breast development
Wide hips
Female-type pubic hair pattern
Small testicular size
Long legs
Behavioural problems
Androgen deficiency
Azoospermia / infertility
Micro genitalia

Question 37

What is the treatment for Klinefelter syndrome?

Answer 37

Lifelong testosterone replacement therapy

Question 38

How common is Turner syndrome?

Answer 38

1 in 2000 live female births

Question 39

What is the triad for Turner syndrome?

Answer 39

Short stature
Streak gonads
Primary amenorrhoea

Question 40

What are the dysmorphia features of Turner syndrome?

Answer 40

Webbing of neck

Cubitus valgus

Question 41

What is the treatment for Turner syndrome?

Answer 41

Growth hormone therapy
Pubertal induction and ongoing hormone replacement therapy
Active monitoring to detect co-morbidities
Assisted conception

Question 42

What is the treatment for gonadotrophin deficiency?

Answer 42

Lifelong testosterone replacement therapy