IVF stands for In Vitro Fertilisation and ET for Embryo Transfer. It is this technique that is used for a variety of infertility problems particularly for male factor problems, endometriosis, advanced maternal age or when the female partner has blocked or damaged fallopian tubes.
IVF is a five-stage procedure:
- Medication Stage
- Monitoring Stage
- Egg Retrieval Stage
- Laboratory Stage
- Waiting Stage
Medication stage:
Two types of medication are used during this stage:
Lucrin (GnRH Antagonist) is a small daily injection that is given under the skin (subcutaneous). This injection commences on the 21st day of the previous cycle (In the Long Course Protocol) and is continued up until the eggs are retrieved. In this protocol Lucrin has two functions; firstly suppresses the release of the bodies' hormones, secondly it prevents early ovulation. In the short course protocol lucrin commences on the second day of the treatment cycle, the control of the cycle is not as strong but premature ovulation will still be prevented.
In the Long Course Protocol the Hormone Injections (FSH or FSH/LH injections) are given intramuscularly (IMI) or subcutaneously (subcut). These injections, given in high doses, commence after the onset of menstruation. The allocated day is flexible and are given for 5 days before the monitoring commences. The function of these injections is to stimulate the ovaries to develop multiple follicles.
In the Short Course Protocol the lucrin commences at the onset of menstruation (on day 2 of the cycle). The FSH or FSH/LH injections commence on day 5 of the cycle to day 9 of the cycle and then monitoring commences. This particular protocol is not flexible.
Monitoring stage:
This stage involves ultrasound scans after five days of hormone injections to determine the number of follicles and the follicle size. Not all follicles contain eggs, the size of the follicle determines the maturity of the eggs. Usually the follicles are small at the first scan, subsequent scans and hormone injections will continue until the leading follicle reaches 18mm or more in size.
Ovulation Injection (Profasi or Pregnyl) - This injection is usually given at a specific time in the evening. Egg retrieval will then take place 38 hours after the ovulation injection, 38 hours is a good 8 hours before the egg is due to be released from the ovary.
Egg Retrieval Stage
The eggs are retrieved from the ovaries while the patient is under strong sedation so that she does not experience pain. The ultrasound machine is in the theatre, a long fine needle is attached to the vaginal probe and gently pushed though the vaginal wall to the follicles on the ovaries. Each follicle is methodically drained the follicular fluid in which the egg is suspended, drains into test tubes. The procedure does not take more than 15 to 20 minutes.
Laboratory Stage
A laboratory scientist using a high powered microscope identifies the eggs immersed in the follicular fluid. The eggs are placed into a dish that has a highly specialised growth medium in place. The medium allows the eggs and later embryos to continue developing as they would in the fallopian tubes. The sperm sample is collected prepared and placed in the medium with the eggs (insemination). Extensive infection tests on both male and female are necessary before the IVF procedure to prevent the growth medium being contaminated. The dish with eggs and sperm are placed in an incubator, fertilisation will occur naturally.
The embryo transfer will be done three to five days after aspiration. After three to five days the laboratory scientists, who have been monitoring embryo development closely, will know which embryos to replace into the uterus. Your doctor will discuss which embryos and the number of embryos to be replaced at this stage. A more accurate estimation of the success rate for the treatment will also be covered. The embryo transfer is a minor procedure requiring no sedation.
Waiting Stage
Extra medication is given to maintain a healthy lining. Emotionally this is a very taxing time. Hormone levels are high and there is not much that can be or cannot be done to influence the outcome of the treatment. Whether there is a pregnancy has been determined physiologically soon after the embryo transfer. It is recommended to resume normal activities in this period. The pregnancy test is done two weeks after the embryo transfer.
In the event of a pregnancy it is essential that you continue on the medications that were prescribed at the time of embryo transfer. If there is no pregnancy it is important to communicate with your doctor. Even though it will be extremely disappointing - remember your doctor has gained valuable diagnostic information throughout the procedure that will guide him in planning future treatment.
IVF vs IUI
Utrasound and Embryo Transfer