Assisted Reproductive Technology (ART)

Question 1

What is infertility defined as ?

Answer 1

Infertility is defined as a failure to concern certain after 1 year of regular unprotected intercourse

Question 2

What is the cause of failure of gamete production or release ?

Answer 2

This can be due to an ovulation,maternal age,PCOS

Azospermia , asthenozoospermia , tetrazoospermia

Question 3

What can cause mechanical blockages to the egg and sperm meeting ?

Answer 3

This can be caused by infection,occlusion of vas deferents or uterine tubes

Previous ligation for sterilisation

Endometriosis

Congenital defects

Question 4

What are some causes of infertility ?

Answer 4

1. Mechanical blockage to egg and sperm meeting
2. Failure of gamete production or release
3. Failure of fertilisation/implantation an miscarriage

Question 5

What are the causes of failure of fertilisation,implantation and miscarriage ?

Answer 5

Genetic factors

Endometrial receptivity and maternal age

Question 6

Define Azoospermia

Answer 6

This is when there is no sperm to ejaculate

Question 7

Define Athenozoospermia

Answer 7

This is when there is reduced sperm motility

Question 8

Define Tetrazoospermia

Answer 8

This is when there is a presence of spermatozoa with over 85% abnormal morphology

Question 9

What statistic of couples are infertile?

Answer 9

There are around 1 in 7 couples

Question 10

What is endometriosis ?

Answer 10

Endometriosis is when tissue similar to the tissue that normally lines the inside of your uterus — the endometrium — grows outside your uterus.These cells will behave the same as when in the uterus.They are shed and will respond to oestrogen.

Endometriosis inside the uterine tube will block them

Question 11

Why does a mechanical blockage in the uterine tubes cause infertility.

How can this be solved ?

Answer 11

This is because this is the site of fertilisation + the first 5-6 days of embryo development takes place here.

This can be fixed by allowing the egg and sperm to meet in vitro.

Question 12

What is endometrial receptivity ?

Answer 12

This is the process which provides the embryo with the chance to attach , invade and develop.

Question 13

What is the word for unknown cause for a disorder?

Answer 13

This means idiopathic

Question 14

How can assisted reproductive technology process begin?

Answer 14

This can start by attempting to :

1. Inducing ovulation using exogenous hormones
2. By passing the uterine tube ((IVF)
3. Direct collection of sperm from the testis/epididymis
4. Direct insertion of the sperm into the egg (ICS)
5. Donor gametes

Combining all of these techniques

Question 15

Define exogenous hormone ?

Answer 15

These are hormones that originate from outside of the body

Question 16

What does IVF stand for?

Answer 16

In vitro fertilisation

Question 17

How does injecting the sperm directly into the egg aid fertilisation?

Answer 17

This can aid fertilisation because it can reduce the effect of motility and in situations where there are no sperm in the ejaculate, a fine needle can be inserted into the testes to aspirate some sperm.

The aspirated sperm are not swimming at this point and can be directly injected into the egg

Question 18

What can we use to induce ovulation ?

Answer 18

We can use gonadotropin in order to induce ovulation

Question 19

How can exogenous gonadotropin be used to induce ovulation?

Answer 19

They can be used to treat women who are anovulatory or who may have oligo/amenorrhoea.

This will induce single dominant follicles

Daily injections and these will be followed by ultrasounds to monitor the cycle

Question 20

Define oligo/amenorrhoea

Answer 20

Oligomenorrhea is the term for infrequent menstrual cycles

(Less than 6-8 periods per year )

Amenorrhoea is a term used to describe the absence of menstruation

Question 21

During a normal cycle what occurs with the oocytes?

Answer 21

There is growth of oocytes and these are producing oestrogen which thickens the lining of the uterus.

Reduction in FSH will lead to most undergoing apoptosis except the dominant follicle which will also contain LHH receptors.

Question 22

What happens when we give women exogenous gonadotrophins ?

Answer 22

If too much FSH is being injected this may stop the dominant follicle being selected as the FSH will remain high.Lots of follicles may reach maturity.This may lead to multiple births.

Question 23

How can we avoid overstimilation of different follicles whilst administrating exogenous gonadotrophins

Answer 23

Patients should be monitered using ultrasound.

Question 24

Why do post menopausal women have high FSH in their urine?

Answer 24

They do not produce oestrogen meaning there is very low inhibition of FSH/LH production.This will become metabolised and will therefore be excreted in urine.

Question 25

How else can you induce ovulation without using exogenous gonadotophins?

Answer 25

This can be done by removing the negative feedback. This is in situations where the Gonaotrophin levels may be normal but no cyclical.

Question 26

What are two ways that we can use to remove the oestodiol feedback?

Answer 26

This can be done by: Blocking the E2 receptor on the pituitary gonadotrophins cells using SERM (Selective oestrogen modulator) e.g: Clomid/Clomiphene -There is still oestrogen present but the pituitary and hypothalamus do not detect this and will produce more FSH/LH. 2.Stop the E2 being made by using an aromatase inhibitor Such as letrozole. Blocking the enzyme aromatase. Aromatase is used to convert testosterone into oestrodiol. This will therefore remove the inhibiting nature of oestrogen .

Question 27

Outline the process of IVF

Answer 27

1.Hypothalaiic-pituitary down regulation (GnRH) (It is pulsatile so quick administration will favour LH) This will prevent pre-maturation 2.Ovarian stimulation (monitoring follicles) 3.hCG trigger 4.Oocyte retrieval 5.Fertilisation in vitro 6.Embryo culture 3-5 days 7.Embryo /blastocysts transfer 8.Pregnancy confirmation 9.Luteal phase support -Cyclogest progesterone

Question 28

How does the selection of a single follicle occour?

Answer 28

There are antral follicles which are growing and not FSH dependent. They will reach the small antral phase and express FSH receptors.They are all recruited when FSH attached to the receptor. As they are growing they will begin to release oestrogen which will cause an inhibition of FSH.The most advanced follicle will then have slightly more FSH receptors and will also contain LH receptors. Dominant follicle. There will be apoptosis of the unrequired follicles

Question 29

How does follicle selection differ in IVF and lead to multiple selection

Answer 29

Follicle selection will lead to multiple follicle selection as exogenous gonadotrophin are being administrated. GnRH is continuous not pulsatile and will therefore cause a shut down of the axis. Additionally as FSH is being administrated the effect of oestrogen is very low. This will allow multiple follicles/

Question 30

How is ovaria stimulation controlled.What does the patient need to do ?

Answer 30

The patient will inject themselves with FSH/LH.Subcutaneously. This occours following down-regulation of the HPG axis. This is done using GnRH antagonists and agonists. Follicle growth is required to be monitored using an ultrasound until the follicles reach 12-19mm length.At this point the hCG trigger will be given. GnRH agonist or kisspeptin. 36 hours will be given to allow for completion of meiosis 1 and the initiation of meiosis 2 before eggs collected.

Question 31

What will occur at ovulation to increase fertility?

Answer 31

The LH surge will cause resumption of meiosis 1 . Meiosis stops and will be resumed pat puberty in particular following ovulation.

Question 32

Why is LH not administred to patients

Answer 32

This is because it has a very short half life.Instead hCG will be administered instead.This is used to trigger meiosis 2.

Question 33

How is oocyte retrieval carried out?

Answer 33

This is done by collecting mature eggs from the ovary using transvaginal needle aspiration under ultrasound guidance.

Question 34

At what point will oocyte retrieval take place?

Answer 34

This will take place 34–38 hours post hCG trigger.

Question 35

How does sperm prepeatrtion take place for IUI and IVF?

Answer 35

This