In Vitro Fertilisation enables us to achieve higher success rates than in conceiving naturally. In many cases, over 60% per attempt.
In Spain, In Vitro Fertilisation is controlled by legislation that demands the couple formally give their informed consent authorising the clinic to carry out analyses to guarantee the health of any future offspring (for example, syphilis, different types of hepatitis, HIV).
An IVF cycle has different stages:
This process ensures that IVF is the correct solution to the patients’ infertility problems and that they are physically and psychologically ready to begin the cycle. If this is not the case, the patients are offered other treatment options.
In order to maximise the possibility of pregnancy, we need to obtain more than one oocyte, which is the number a woman’s ovary normally produces. In order to stimulate the production of several oocytes and guarantee their quality, we provide a combination of medicines whose response is monitored by means of vaginal ultrasound scans and, occasionally, blood tests.
The whole process lasts, depending on each case, approximately between 8 and 12 days. The treatment can be cancelled if a low or indeed exaggerated ovarian response is observed.
Once the oocytes are mature, we retrieve them with the help of a vaginal ultrasound scan, under local anaesthesia and light sedation; that is to say, totally painlessly. This process only takes 15 minutes and does not require an operation, being hospitalised, stitches or the use of general anaesthesia.
The retrieved eggs are taken into the IVF laboratory where they are prepared to be inseminated. At the same time, the semen is activated to improve its fertilisation potential. Oocytes and spermatozoids are placed together over a period of several hours within an incubator which provides ideal conditions for fertilisation to take place and the subsequent development of the pre-embryos. The number of fertilised eggs will not be known until the next day but overall the fertilization rate is 60%. For this reason several embryos usually develop.
The phase of embryo culture can last between two to five days. This enables us to observe the embryo development in order to select the ones of highest quality. Nature will reject the weaker ones. In general, during a longer culture period, we have fewer viable embryos but they are of much better quality than the embryos achieved during a short culture period.
The implantation rate, that is to say, the percentage of embryos that take hold in the uterus, is generally between 40 and 50%. In order to avoid multiple pregnancies we propose in many cases to transfer only one embryo and freeze the rest. The embryos are placed in the uterus in a fast, comfortable and painless procedure.
If more viable embryos remain, they are cryopreserved. That is to say, they are frozen to allow for future transfers, either if pregnancy does not occur following the first transfer and the procedure needs to be repeated or otherwise, to allow the couple the option to have another child at a later date without having to undergo the IVF process from the beginning. The pregnancy rate obtained after cryopreservation is 40%.
The fact of having viable embryos does not necessarily mean that a pregnancy will develop. Unfortunately, the implantation rate in human beings is not so high and not all transfers develop into a pregnancy. In most cases it is not possible to know why embryo transfers have not succeeded, because in a natural pregnancy the number of embryos that do not implant is very high. Currently this is the basis of many scientific studies.
Our goal is not to obtain multiple pregnancies but to obtain the highest rate of success per cycle. Nevertheless, since the embryo does not always implant, we transfer in many cases two or three embryos. Transferring more embryos is not entirely beneficial as there is a risk of multiple pregnancy.
Once gestation has been attained, the pregnancy will develop with total normality, without requiring special controls except for the usual attention paid to much wished-for pregnancies. Please note that the possibility of miscarriage, malformations, etc. is the same as for naturally-achieved pregnancies.
If treatment finishes and pregnancy has not been achieved, the Committee on Reproduction, formed by the team responsible for the case, will reevaluate the situation to advise the patients on the subsequent steps to be taken. For that purpose, a personal interview with the couple takes place.
The above information can be modified due to the constantly evolving law and medical changes that occur in Reproductive Medicine and due to the specific characteristics of each case. At Instituto Bernabeu, our doctors, biologists, nurses, laboratory and administration staff all do their best to help the couple achieve our common goal: the birth of a healthy child.