IVF

Question 1

In vitro fertilisation

Answer 1

Fertilising an egg with sperm in a lab, then injecting the resulting embryo into the uterus

Question 2

Success of IVF

Answer 2

25 – 30% success rate

Question 3

Intrauterine insemination

Answer 3

Involves injecting sperm into the uterus

Question 4

When is intrauterine insemination used

Answer 4

HIV
Same sex couples
Problems with vaginal sex

Question 5

Criteria for funding IVF

Question 6

What does a cycle of IVF involve

Answer 6

1. Ovarian stimulation and collection of oocytes (eggs).
2. Oocyte penetrated by sperm
3. Embryos transferred separately in multiple attempts at pregnancy

Question 7

What happens to embryos not used immediately

Answer 7

Frozen to be used at a later date

Question 8

Process of IVF

Answer 8

1. Suppressing the natural menstrual cycle
2. Ovarian stimulation
3. Oocyte collection
4. Insemination / intracytoplasmic sperm injection (ICSI)
5. Embryo culture
6. Embryo transfer

Question 9

How to suppress the natural menstrual cycle

Answer 9

GnRH agonists

GnRH antagonists

Question 10

GnRH agonist protocol

Answer 10

Injection of a GnRH agonist (e.g. goserelin) given in the luteal phase of the menstrual cycle - 7 days before the expected onset of the menstrual period (usually day 21 of the cycle).

Initially stimulates the pituitary gland to secrete a large amount of FSH and LH.

After initial surge, there is negative feedback to the hypothalamus

This causes suppression of the menstrual cycle

Question 11

GnRH antagonist protocol

Answer 11

Daily subcutaneous injections of a GnRH antagonist (e.g. cetrorelix) are given

Starting from day 5 – 6 of ovarian stimulation

Suppresses release of LH therefore no ovulation

Question 12

Why is suppression of the normal menstrual cycle done

Answer 12

Without suppression, ovulation would occur and the follicles that are developing would be released before it is possible to collect them

Question 13

Ovarian Stimulation

Answer 13

Using FSH injections to promote the development of multiple follicles in the ovaries.

Question 14

When is ovarian stimulation done

Answer 14

Beginning of the menstrual cycle usually day 2

Question 15

What does ovarian stimulation involve

Answer 15

Subcutaneous injections of FSH over 10 to 14 days

Transvaginal USS scans for monitoring

When enough follicles have developed to an adequate size, FSH is stopped

Injection of HCG is given 36 hours before collection of the eggs

Question 16

How does ovarian stimulation therapy work

Answer 16

The FSH stimulates the development of follicles which is closely monitored with regular transvaginal ultrasound scans

Human chorionic gonadotropin stimulates the final maturation of the follicles, ready for collection

Question 17

Oocyte Collection

Answer 17

Using transvaginal USS, a needle is inserted through the vaginal wall into each ovary to aspirate the fluid from each follicle.

This fluid contains the mature oocytes from the follicles.

The procedure is usually performed under sedation (not a general anaesthetic).

The fluid from the follicles is examined under the microscope for oocytes

Question 18

Oocyte insemination

Answer 18

A sperm sample and the egg are mixed in a culture medium

Thousands of sperm combined with each oocyte to produce enough enzymes (e.g. hyaluronic acid) for one sperm to penetrate the corona radiata and zona pellucida and fertilise the egg

Question 19

Embryo Culture

Answer 19

Dishes containing the fertilised eggs are left in an incubator and observed over 2 – 5 days to see which will develop and grow.

Monitored until they reach the blastocyst stage of development (around day 5)

Question 20

Embryo Transfer

Answer 20

Highest quality embryos are selected for transfer.

A catheter is inserted under ultrasound guidance through the cervix into the uterus.

A single embryo is injected through the catheter into the uterus, and the catheter is removed

Question 21

When is a pregnancy test performed

Answer 21

Around day 16 after egg collection - shows success of implantation

Question 22

Progesterone

Answer 22

Used from the time of oocyte collection until 8 – 10 weeks gestation

In the form of vaginal suppositories.

Mimics progesterone that would be released by the corpus luteum during a typical pregnancy.

From 8 – 10 weeks the placenta takes over production of progesterone, and the suppositories are stopped

Question 23

Ultrasound scan

Answer 23

Performed at 7 weeks to check for the fetal heartbeat and rule out miscarriage or ectopic pregnancy

Question 24

Complications of IVF

Answer 24

Failure
Multiple pregnancy
Ectopic pregnancy
Ovarian hyperstimulation syndrome

Question 25

Risk of egg collection procedure

Answer 25

Pain
Bleeding
Pelvic infection
Damage to the bladder or bowel