This fantastic ABC Science Animated IVF animation takes you through the 7 steps of in vitro fertilisation. Please click on “Enter Site >” on the video above to watch the interactive video.
Here is the transcript:
In Vitro Fertilization
In vitro fertilization (IVF) is a reproductive technology in which an egg is removed from a woman and joined with a sperm from a man, in vitro (outside of the body, or literally, in glass).
The sperm and egg cells fuse to form a single cell, or zygote, which then starts dividing to form an embryo. When the embryo is only a few cells large, it is implanted into the woman’s uterus, and, if successful, will develop as a normal embryo.
IVF is used to treat cases of infertility such as occlusion (blockage) of the fallopian tubes, endometriosis (abnormal tissue growth in this case outside the uterus), abnormal sperm, and in some cases of unexplained infertility.
Amongst the Australian population, more than 1% of people were conceived using the IVF technique.
In this interactive, we examine the IVF cycle and detail each step of the procedure.
Step 1: Establishing Legitimacy For Treatment
Initially, routine fertility tests are performed to assess the degree of infertility that either partner may be experiencing. Such tests include blood tests, semen analysis and pelvic ultrasounds.Once the results of the tests have been analysed by a fertility specialist, a treatment program is identified.
Before treatment begins couples may be required to attend a counselling session. In the state of Victoria in Australia, attendance at one such session is a legal requirement, but in other states it is only advisable that couples participate. During these counselling sessions couples are provided with information about all aspects of the treatment to be received. They also provide an opportunity to discuss with a registered psychologist potential emotional stresses or concerns about infertility treatments. However these counselling sessions are not designed to assess your suitability for infertility treatment.
If you are using donor eggs or sperm, identification issues will need to be discussed with the counsellor.
In addition to the counselling session, a decision will need to be taken on the number of embryos transferred and whether or not additional embryos not used in the initial IVF procedure should be cryogenically preserved (frozen) for use at a later date.
The number of embryos transferred has been an intense point of discussion worldwide. In Australia, generally one to two embryos are transferred. The more embryos transferred the greater the chance of achieving a pregnancy. However, this increases the risk of a multiple pregnancy occurring (eg. twins or triplets). Multiple pregnancies are associated with an increased risk to the health of the babies and mother. The chance of a multiple pregnancy varies with age, the chances are higher if you are relatively young (for instance, under 30) but are lower if you are over 40.
In general, 2-4 IVF cycles may need to be planned for, in order for pregnancy to be successful.
Step 2: Regulating & Optimising Egg Growth
An oral contraceptive pill is taken for a minimum of 21 days, to help regulate the menstural cycle and co-ordinate the timing of follicle growth. Eggs grow within a multicellular unit called a follicle in the ovary.
In order to stimulate the growth of many follicles in the ovary, injections of a hormone called FSH are given for 10-12 days. The more eggs that can be collected from the ovary the greater the chance the required number of embryos will be produced.
During this time, one or two ultrasounds will be performed to find out how many follicles are growing, the size of the follicles and in which ovary they are developing.
Step 3: Controlling Egg Maturation & Release
When the eggs are big enough, daily injections of Lupron are given to stop the eggs being released from the ovary too early. The timing of egg collection is based upon levels of oestrogen (produced by the follicles) present in the blood, as well as the ultrasound results. When the eggs are nearly ready for collection, a hormone called hCG is given by injection, which stimulates the final maturation of the egg. Eggs are collected 36 hours later.
Step 4: Egg Collection And Incubation
Egg collection is a day procedure that is carried out in hospital. A light anesthetic is given, and the follicles are visualized in the ovary using ultrasound. A needle is used to collect the egg from inside each follicle. With the aid of the ultrasound, the needle is pushed through the vaginal wall and into the ovary. The eggs are removed and then put into a special solution in sterile dishes and placed into an incubator in preparation for fertilization.
Step 5: Sperm Collection & Fertilization
The male partner will then be asked to provide a sample of his semen close to the time of egg collection. Contained within this sample, are the sperm to be used in fertilization, which are then washed and prepared. The most motile sperm will be added to the eggs for fertilization to occur. Fertilization should occur 18 – 24 hours later. If more than one embryo is produced, they may be cryogenically preserved for use in successive IVF cycles, or, for example, as a precaution against future infertility. There is a limit to the number of years embryos can be stored in a frozen state and this is subject to legislation, which differs from state to state in Australia.
Step 6: Transfer Of Embryo To The Uterus
Egg collection is a day procedure that is carried out in hospital. A light anesthetic is given, and the follicles are visualized in the ovary using ultrasound. A needle is used to collect the egg from inside each follicle. With the aid of the ultrasound, the needle is pushed through the vaginal wall and into the ovary. The eggs are removed and then put into a special solution in sterile dishes and placed into an incubator in preparation for fertilization.
Step 7: Confirmation Of Pregnancy
Egg collection is a day procedure that is carried out in hospital. A light anesthetic is given, and the follicles are visualized in the ovary using ultrasound. A needle is used to collect the egg from inside each follicle. With the aid of the ultrasound, the needle is pushed through the vaginal wall and into the ovary. The eggs are removed and then put into a special solution in sterile dishes and placed into an incubator in preparation for fertilization.
Resources
To view this interactive IVF animation on the ABC’s website please go to:
https://www.abc.net.au/science/lcs/ivf.htm