Repro

Question 1

What is the age of onset of puberty in girls?

Answer 1

9-13

Starts with growth spurt and breast growth
Menarche starts at 13

Question 2

What is the age of onset of puberty in boys?

Answer 2

10-14

Starts with growth spurt and increased testicular volume

Question 3

What initiates puberty?

Answer 3

Pulsatile release of GnRH from the hypothalamus

This stimulates release of LH and FSH from the anterior pituitary

This stimulates release of androgens and oestrogen

Question 4

What stimulates Leydig cells in the testes and what do they produce?

Answer 4

LH stimulates Leydig cells to produce testosterone

Production remains constant

Question 5

What stimulates Sertoli cells and what do they produce?

Answer 5

Stimulated by testosterone (from Leydig cells)

Site of spermatogenesis
Also secretes inhibin for -ve feedback on anterior pituitary, reduce FSH

Located in seminiferous tubule

Question 6

What cells in the ovaries respond to FSH?

Answer 6

Ovarian granulosa cells

Stimulates production of oestrogen production

Question 7

What cells in the ovaries respond to LH?

Answer 7

Theca interna cells

Stimulates production of progesterone

Question 8

What is the effect of different levels of oestrogen on GnRH?

Answer 8

Low levels - negative feedback on GnRH

High levels - positive feedback on GnRH, causes LH surge

Question 9

What is the effect of progesterone?

Answer 9

Increases inhibitory effect of oestrogen
Prevents +ve feedback, so no LH surge

Prevents further ovulation

Question 10

Where is inhibin produced in the ovary? And what is its effect?

Answer 10

Released from granulosa cells of corpus luteum

Inhibits secretion of FSH => only one egg develops
Also has a small inhibitory effect on LH

Question 11

What are the stages of the ovarian cycle?

Answer 11

Follicular phase
Ovulation
Luteal phase

Question 12

What occurs in the follicular phase?

Answer 12

Increasing FSH;
Causes follicular development 
Theca interna and externa now appears
Follicle now able to secrete oestrogen 
Inhibin starts to be secreted, inhibits FSH 

Increasing oestrogen;
Rise causes positive feedback on LH
Causes LH surge => progesterone production

Question 13

What occurs in ovulation?

Answer 13

Meiosis I completes
Meiosis II starts
Mature oocyte extruded through capsule of ovary

Question 14

What occurs in the luteal phase?

Answer 14

Granulosa and theca cells become the corpus luteum which secrets oestrogen and progesterone
Progesterone counteracts the +ve feedback of oestrogen => reduced LH
FSH inhibited by inhibin

If fertilisation doesn’t occur, corpus luteum becomes the corpus albicans

Question 15

What are the stages of the uterine cycle?

Answer 15

Proliferative phase

Secretory phase

Question 16

What occurs in the proliferative phase?

Answer 16

Proliferation and thickening of the endometrium in response to oestrogen - functional layer doubles in size

Glands within the endometrium become coiled

Question 17

What occurs in the secretory phase?

Answer 17

The glands become secretory due to progesterone
Glands lose their structure after hormones begin to fall
If implantation doesn’t occur then the functional layer is shed

Question 18

What is the function of GnRH?

Answer 18

Released in pulses by the hypothalamus
Stimulates LH and FSH

Can become desensitised with constant exposure - given in endometriosis

Question 19

What is the function of FSH?

Answer 19

Stimulates follicle development at the start of the cycle

Sustains development of a gamete

Question 20

What is the function of LH?

Answer 20

Responsible for ovulation - LH surge

Question 21

What is the function of inhibin?

Answer 21

Inhibits FSH

Produced by follicles

Question 22

What is the function of oestrogen?

Answer 22

Promotes fertilisation

Proliferation of endometrium and myometrium
Fallopian tubes motility
Production of thick, alkaline cervical mucus

Question 23

What is the function of progesterone?

Answer 23

Sustains a viable pregnancy

Secretory function of the endometrium
Reduced motility of myometrium
Production of thick, acidic cervical mucus - prevents further entry of sperm

Question 24

What methods are used in contraception?

Answer 24

Blocks transport of sperm
Disrupts HPG axis
Inhibits implantation of conceptus

Question 25

What are some natural contraception methods?

Answer 25

Abstinence
Withdrawal
Fertility apps

Lactational amenorrhoea - breastfeeding delays return of ovulation

Question 26

What are barrier methods of contraception?

Answer 26

Male/female condoms

Diaphragm

Question 27

How does the COCP work?

Answer 27

Prevents ovulation
Reduces endometrial ability for implantation
Thickens cervical mucus

Question 28

What are some examples of high dose progesterone contraception? And how do they work?

Answer 28

Progesterone depot
Progesterone implant

Inhibits positive feedback of oestrogen => no LH surge => no ovulation
Also thickens cervical mucus and prevents endometrial proliferation

Question 29

How does low dose progesterone work as contraception?

Answer 29

Thickens cervical mucus

Question 30

What methods of contraception prevent implantation?

Answer 30

Intrauterine system - IUS
Plastic device which secretes progesterone
Reduces endometrial proliferation and thickens cervical mucus

Intrauterine device - IUD
Plastic device with added copper
Copper is toxic to sperm
Endometrial inflammatory response also prevents implantation

Question 31

What methods of sterilisation are there?

Answer 31

Vasectomy - vas deferens cut or tied to prevent sperm entering ejaculate

Tubal ligation/clipping - Fallopian tubes cut or tied off, can be done under local or general

Question 32

What methods of emergency contraception are there?

Answer 32

Emergency IUD

Emergency pill