Assisted Reproductive Techniques
Assisted Reproductive Techniques are procedures whereby an oocyte (egg) is removed from the body of a women, manipulated and then returned to the body.
There are basically 2 techniques that are performed namely:
IVF –Invitrofertilization : There are several principles in IVF
Naturally a woman produces only 1 mature follicle with an egg in it and that is the reason why most women deliver only 1 child. However in IVF, the aim is to induce ovulation so as to collect as many eggs as possible. The reason for doing this is that, the more eggs is collected and fertilized, the more embryos can be obtained and thus the best embryos can be transferred into the uterus and the remaining can be frozen. This is called superovulation.
OOCYTE RECOVERY (OR OOCYTE PICK UP)
This procedure can be performed under just sedation or sometimes under general anaesthesia. The procedure has been simplified by the use of a transvaginal ultrasound. A needle is passed with the assistance of a transvaginal ultrasound and the follicles are aspirated. The embryologist will look for the eggs (oocytes) in this follicular fluid.
The male partner will need to produce a semen sample at the same time as oocyte recovery is done. The semen is then prepared to extract all motile sperm in the sperm laboratory.
The oocytes and the sperm are then mixed in a culture media and placed in an incubator. The next day the embryologist will look for evidence of fertilization by looking at the pronuclear state. The embryos are then seen every day until the day of embryo transfer.
The fertilized embryos are then transferred into the uterine cavity using a fine catheter. This procedure does not require any anaesthesia.
ICSI – intracytoplasmic sperm injection
INTRACYTOPLASMIC SPERM TRANSFER
All the principles are the same as for IVF except for no. 4
In ICSI, a sperm is injected into the oocyte (egg) using a fine needle. This is usually done when there is a low sperm count or in cases where there is no sperm at all (azoospermia) when sperm are obtained from the testes.