In vitro fertilisation (IVF) involves uniting the ovum (egg) with the spermatozoid inside glass – in vitro – in order to achieve a number of embryos to transfer to the mother’s uterus.
This technique is carried out in a laboratory with the latest technology and is used when previous kinds of treatment
such as Artificial Insemination have failed. It is also the solution to sterility problems arising from the male factor and Fallopian tubes factor (obstructed tubes), among others.
The insemination of oocytes can be carried out by means of the conventional IVF technique or by Intracytoplasmic Sperm Injection (ICSI). The latter is recommended in cases of severe masculine sterility, previous fertilisation failures with IVF, previous Artificial Insemination
treatment failures, or situations in which we have a limited number of oocytes available.
There are various phases to the procedure
Personalised assessment of the patient
In our clinics we provide the patient with a personalised diagnosis to be able to choose the best treatment for each infertility problem. To do so, we examine our patients as regards their family precedents, body mass index, ovarian reserve, etc.
This procedure is necessary to increase the chances of success, since a woman only produces one follicle naturally – and therefore one oocyte – in each menstrual cycle. This treatment attempts to stimulate the ovary to produce more oocytes than it would naturally and thereby obtain a greater number of embryos. The treatment lasts between 12 to 20 days according to the protocol used and each patient’s speed of response. Meanwhile, a series of 3 or 4 ultrasound scans are carried out and the amount of estradiol in the blood is determined to check that there is normal growth and development of the follicles.
When we have evidence through the ultrasound scans that the follicles have reached an adequate size, and we consider that there are a suitable number of oocytes, we schedule follicular puncture 36 hours after administering the injection of hCG that induces the oocytes to reach their final maturity. Puncture is carried out in the operating theatre under sedation so that the patient does not feel any kind of discomfort during the procedure, which lasts approximately 10-15 minutes.
Insemination of the oocytes
Once we have the oocytes after follicular puncture, and the spermatozoa, which are normally obtained from a semen sample from the male partner, insemination of the ova (eggs) begins. This process can be performed via conventional IVF, which involves placing an oocyte surrounded by spermatozoa in a culture plate, or else via ICSI, which consists of inserting a live spermatozoon into the oocyte by puncturing the latter with the aid of a pipette.
Embryo culture in the laboratory
The resulting embryos are observed in the laboratory day after day and are classified according to their morphology and their ability to divide. Some embryos can become blocked in their development, and these will be discarded as they are considered to be non-viable.
This involves inserting the best embryos from the cohort into the mother’s uterus with the help of a specially designed cannula. The procedure is carried out in an operating theatre, although in this case it is not necessary to use sedation since it is a quick, painless procedure.
Vitrification of the remaining embryos
Once the embryo transfer has been made, we vitrify the remaining good quality embryos so that they may be transferred in a later cycle without the need for ovarian stimulation. The new technique of fast freezing or vitrification, which we carry out in IVI
, ensures promising results since the embryos are not affected by this and the gestation rate does not drop, as happens with slow or conventional freezing, with respect to the rate obtained with fresh embryos.
Approximately 2 weeks after the embryo transfer, the patient must undergo a test for beta-hCG in her blood to check if gestation has been achieved and to quantify the amount of the pregnancy hormone in the blood. If the test is positive, a vaginal ultrasound scan must be performed in order to view the gestational sac.