In vitro fertilisation is a set of methods for fertilising an oocyte (egg) with the sperm of a partner or anonymous donor outside of the woman’s body. It is preceded by the hormonal stimulation necessary for the maturation of several eggs at the same time, which are then extracted via an oocyte retrieval. After the eggs are fertilised in a laboratory, the embryo created is transferred into the uterus.
The course of treatment can vary between patients, which is why a specialist always prepares a personalised stimulation protocol. In most cases, the process begins with hormonal stimulation on the second day of the menstrual cycle, and takes 10 days. Stimulation medication is administered with an injector pen and a nurse-coordinator always explains the exact process and dosage to the patient. It is necessary to come to the clinic twice during stimulation to check the maturation of follicles with eggs, mainly their size and number, but also the thickness of the endometrium. This allows the physician to determine the exact time for extracting the eggs, as well as to administer the last injection needed for their maturation.
Mature oocytes are retrieved on the 12th day of the menstrual cycle. The eggs are extracted under short-term general anaesthetic via the vagina with a special puncture needle guided by ultrasound. After extraction, the woman remains on bed rest for about 2 to 3 hours. On the same day, her partner supplies his ejaculate, which is then processed, and the sperm is used to fertilise the extracted eggs.
The eggs can be fertilised using the standard method or the ICSI method, with the sperm processed by some of the separation methods. The standard method consists of adding a sperm sample to the eggs, where the sperm cells penetrate the egg on their own, just as in natural conception. This method is suitable when the partner’s semen analysis results look good. In the case of poor results, the ICSI method is recommended.
Embryos created this way are stored for cultivation in an incubator, where their development is continuously monitored. Given that health insurers in Slovakia reimburse only three-day cultivation, the price for private clients also includes only three-day cultivation. However, the embryo usually reaches the blastocyst stage on the fifth day. Some embryos stop developing during this time for various, mainly genetic, reasons. In such cases, the embryo would not implant after natural conception. Embryos which reach the blastocyst stage thus have a significantly higher chance of implanting successfully. Because of this, we offer the option of prolonged cultivation. This is necessary also if the couple is interested in a pre-implantation genetic test, because a sample can be taken only in the blastocyst stage.
Fresh embryos are inserted (embryo transfer) after three days at the earliest, or in the case of prolonged cultivation, after five days (i.e., day 17 of the menstrual cycle). The remaining embryos are frozen (vitrified) and used if other transfers are needed later (cryo-embryo transfer). Only embryos which have reached the blastocyst stage can be vitrified. The embryo is transferred using a thin catheter through the cervix directly into the uterine cavity. Only one embryo is transferred, as transferring multiple embryos does not significantly influence the success rate; however, it does significantly increase the chances of multiple pregnancy. The intervention takes approximately 10 minutes and is painless. The patient can go home immediately afterwards.
A pregnancy test is done two weeks after the embryo transfer. Supportive treatment is administered during this period to increase the probability of successful conception. Spotting can occur in some cases, but that does not mean the cycle was unsuccessful. The pregnancy test may still be positive, so it is important not to stop taking the medication arbitrarily and to contact the coordinator first in case of any doubts.
Unlike the standard IVF cycle, a patient undergoing a natural IVF cycle does not take any hormonal stimulation and the physician monitors the maturation of follicles during the patient’s natural cycle. In this case usually only one egg matures, which is also why a general anaesthetic is not needed for the extraction.
Given that only one egg (two at most) is available during a natural IVF cycle, the probability of successful treatment is lower than in a classic IVF cycle, in which more eggs are retrieved. Not every egg is successfully fertilised in a laboratory and some of the eggs do not necessarily reach the blastocyst stage, especially if the semen analysis results are not ideal. Therefore, special laboratory methods are suitable for use in the natural IVF cycle, to increase the chances of success, such as the ICSI method with a lower price due to the lower number of eggs in a natural IVF cycle (ICSI NATURAL), or one of the sperm separation methods.
The natural IVF cycle is suitable mainly for women who ovulate regularly but react poorly to hormonal stimulation, for example older patients in whom standard stimulation has no effect. It is also a good choice for women who want to avoid the additional hormonal stimulation associated with a classic IVF cycle.
The procedure for an IVF SOFT cycle is almost the same as for the standard IVF cycle, with the only difference being that lower doses of stimulating medication are used and the hormonal stimulation period is shorter. This means that the stimulation is milder and better tolerated by the woman. However, the number of eggs maturing is directly related to stimulation intensity and the number of retrieved oocytes is thus lower, usually 2 to 5. The probability of a successful cycle is therefore slightly lower compared to standard IVF, for the same reasons as natural IVF cycles. In this case, it also helps to use some of the special laboratory methods such as ICSI to increase chances. The SOFT cycle has a lower price due to fewer oocytes present (ICSI SOFT).
The SOFT cycle is suitable mainly for patients with a higher risk of ovarian hyperstimulation syndrome or who react poorly to hormonal stimulation. This type of cycle is also used for older patients or patients with polycystic ovary syndrome