by Dr Ioannis Giakoumakis
IVF procedure is not one simple, but a series of several medical and laboratory steps.
The steps involved in this procedure are:
- Ovarian stimulation
- Egg retrieval (collection)
- Sperm retrieval
- Embryo transfer
A combination of medications (commonly termed fertility drugs) and hormones are usually given to the woman to stimulate the ovaries and produce more than the usual one follicle (thus egg) per cycle. This is to enable the collection of several follicles (thus eggs) and increase the success of IVF because some eggs may not be fertilize or develop normally after fertilization.
During this step, the follicles are monitored by blood tests and transvaginal ultrasounds that ensure eggs are collected at precisely the right time.
A number of different protocols are used to stimulate the ovaries to produce eggs. These are Short, Long, Flare and Antagonist. The protocol chosen by your doctor will depend upon your age, FSH level and previous response (if applicable).
Oocyte Retrieval (egg collection)
The egg collection procedure is a relatively easy procedure that is performed in a sterile room (egg collection room) with the presence of an anaesthesiologist, as it requires mild anaesthesia. The procedure takes about 10-20 minutes, depending on the number of follicles present at the ovaries. You are advised to be fasting at least for 10 hours and avoid fluid consumption before the egg collection.
During egg collection, the location of the ovarian follicles is successfully spotted with the use of vaginal ultrasound, and then a needle is directed through the vagina wall into the ovarian follicles. As the tip of the needle passes into each follicle, the fluid gets drawn, and the follicle collapses. The fluid is aspirated into multiple tubes, which are then immediately passed to the embryologist in the IVF laboratory where the eggs are identified, isolated, placed in culture medium and in proper temperature.
After the egg collection, the woman can eat normally but she is advised to take a light meal and a lot of fluids. It is recommended to rest at home for the remainder of the day.
During the egg collection, the husband provides a sperm sample. The male partner should abstain from ejaculation for 3 – 5 days to provide the best quality sperm. Masturbation, especially at the clinic, is the preferred method of collection. However, because it is sometimes difficult and stressful, men could bring the semen sample from home or can freeze a sample several days before the day of oocyte retrieval (fresh samples are always preferred). In cases of men with azoospermia, spermatozoa maybe retrieved directly from the testis (surgical sperm retrieval). The embryologist places the sperm sample at an incubator (37οC) for a short period of time and following a semen assessment the process of “washing of the sperm” takes place in order to isolate the “best looking” sperm. If donor sperm or frozen sperm will be used, the sample will be taken from the freezer and prepared in the same way.
Several hours following egg retrieval and semen preparation, fertilization occurs in the embryology lab. To begin the fertilization process, the eggs are placed in a petri dish containing a solution rich in specialized nutrients for 2 to 3 hours. The washed sperm is incubated together with the eggs for 16-20 hours in 37οC. The next morning, the embryologist will examine the eggs to see which have fertilised. The eggs that have been fertilized are now called embryos and are incubated in special laboratory conditions for an additional 48 -96 hours, depending on the stage of embryo your doctor is recommending for transfer. The fertilization rate is usually 80-100%. Alternatively, patients dealing with male infertility problems are offered the choice of Intra Cytoplasmic Sperm Injection (ICSI).
Embryo transfer is a procedure that does not require anaesthesia. Three to five days following fertilisation the best quality embryos, according to morphological criteria, are selected in order to be placed into the woman’s uterus. The selected embryos are inserted into a thin tube (catheter) and guided towards the woman’s uterus. One to three embryos can be transferred depending of the age and the medical record of the recipient. Sometimes couples have extra embryos available after an IVF procedure. In such cases, couples may decide on cryopreservation (freezing) to store embryos a future IVF cycle. If cell divisions carry on for between five to six days, the embryos reach the blastocyst stage. At this point embryologists can have a good indication of which are the embryos able and most likely to result in a successful pregnancy once they transfer them back into your uterus.
It is not unusual to see vaginal blood spotting prior to the pregnancy test. Approximately 50% of our patients experience very mild bleeding (few blood spots) prior to the pregnancy test or even afterwards.
Rest is recommended for 24 to 48 hours after the embryo transfer.
* You must do the pregnancy test even if you have seen a few spots of blood.