Sex Steroids

Question 1

Name the three major sex hormones

Answer 1

Oestrogen, progesterone, testosterone

Question 2

What are the major effects of oestradiol (strongest of the oestrogen hormones)?

Answer 2

Stimulates growth of the endometrium and breast

Stimulates production of progesterone receptors

Question 3

What are the major effects of progesterone?

Answer 3

Stimulates growth of the endometrium and breast
Maintains pregnancy
Inhibits production of oestrogen receptors

Question 4

What are the major effects of testosterone?

Answer 4

Stimulates male characteristics:

Hairy body, deep voice, anabolism, aggression

Question 5

Sex steroids are synthesised from what?

Answer 5

Cholesterol

Question 6

Oral contraceptive pills exist in two types, what are they?

Answer 6

COCP (combined oral contraceptive pill)

POP (progestin only pill)

Question 7

In which three ways can the COCP be administered?

Answer 7

Monophasic - each tablet has fixed amount of oestrogen and progesterone (21 days)

Biphasic - fixed oestrogen, progestin increases in second half of cycle (21 days)

Triphasic - amount of oestrogen fixed or variable, progestin increases in 3 equal phases (21 days + 7day placebo)

Question 8

What is the mode of action of the COCP?

Answer 8

Suppresses ovulation by inhibiting FSH and LH
Holds ovary in non-dominant follicular state
Adverse effect on cervical mucus (more viscous)
Adverse effect on endometrium (remains atrophic)

Question 9

Give some ADRs of the COCP

Answer 9

Venous thromboembolism 
MI 
Hypertension 
Decreased glucose tolerance 
Mood swings 
Headaches

Question 10

Why should you be careful when prescribing COCP alongside certain other medications?
Give some examples of such medications

Answer 10

The COCP is metabolised by CYP450
Therefore efficacy is reduced by enzyme inducing drugs such as: Anti-epilepsy drugs- Carbamazepine/phenytoin
Antibiotics - Rafampicin, Rifabutin
St John’s Wort

Question 11

How does the POP work as a contraceptive?

Answer 11

Suppression of oestrogen
Thickens cervical mucus
Endometrium remains thin

Question 12

What is the definition of a “missed pill”?

Answer 12

A missed pill >24 hours after the time it was meant to be taken

Question 13

If one pill is missed, what is the general advice?

Answer 13

Take the missed pill immediately, even if it means taking two pills in one day
Continue taking the rest of the pack as normal

Question 14

If two pills are missed, what is the general advice?

Answer 14

Take the missed pill immediately, even if it means taking two pills in one day
Continue taking the rest of the pack as normal
USE EXTRA CONTRACEPTION FOR THE FOLLOWING SEVEN DAYS

Question 15

Which emergency contraception can be taken up to 72hours post coitus?

Answer 15

Levonorgestrel 1.5mg

Question 16

Which emergency contraception can be taken up to 120 hours post coitus?

Answer 16

EllaOne 30mg

Copper IUD

Question 17

Which two types of post menopausal hormone replacement therapy exist?

Answer 17

ERT (oestrogen replacement therapy)

HRT (hormone replacement therapy)

Question 18

Why might we prescribe HRT?

Answer 18

To relieve symptoms auch as hot flushes, sweats, vaginal dryness, dysparenuia
Prevent osteoporosis

Question 19

HRT is NOT prescribed to reduce the risk of __________

Answer 19

heart disease

Question 20

Explain some of the risks of ERT and HRT

Answer 20

ERT: unopposed oestrogen- increased risk of developing endometrial and ovarian cancer
HRT: opposed oestrogen- increased risk of developing breast cancer
Increased risk of stroke and ischaemic heart disease
Increased risk of venous thromboembolism

Question 21

What is clomiphene used for and how does it elicit its effect?

Answer 21

Induction of ovulation
Inhibits oestrogen binding in the anterior pituitary which inhibits negative feedback and therefore increased FSH and LH expression

Question 22

What is the drug tamoxifen used for?

Answer 22

Reduces breast cancer risk

Induces ovulation

Question 23

What is the drug mifepristone used for?

How does the drug produce this response?

Answer 23

Termination of pregnancy
Induction of labour

Makes the uterus more sensitive to prostaglandins

Question 24

What are selective oestrogen receptor modulators (SERMs) and when might they be used?

Answer 24

e.g. Raloxifene

Drugs protect against osteoporosis

Question 25

What is the drug finasteride used for?

Answer 25

Hair loss prevention - male pattern baldness

Benign prostatic hyperplasia