Embryo care at the reproductive clinic
During a single cycle of in vitro fertilisation, a number of eggs are collected and subsequently fertilised with sperm. If fertilisation is successful, doctors have at their disposal several usable embryos that can be used for transfer. Currently, only one embryo is normally used in order to avoid multiple pregnancies. So what happens to the other embryos and how are they looked after?
Frozen embryo transfer (FET) means more chances
During a single cycle of IVF several eggs are taken, as this procedure is quite a demanding one for a woman's body. The eggs are fertilised after collection, and if all goes well, embryos are created from them. Currently, IVF isperformed with the use of only one embryo in the transfer. This minimises the risk of multiple pregnancies. The remaining eggs then need to be looked after.
Every reputable reproduction clinic offers its clients the option of freezing embryos (vitrification). In this process, embryos are frozen and preserved for the future. Frozen embryos can then be used if the embryo transfer fails on the first attempt or clients wish to conceive another child by IVF in the future.
Success rate of KET
Recently frozen embryos can be used for frozen embryo transfer (FET). Embryos can be thawed repeatedly and transferred to the uterus. This technology increases the effect of a single IVF cycle paid for by the insurance company. However, the freezing of embryos in itself is not covered by insurance companies and the price of the procedure depends on the specific price lists of reproduction clinics. This is usually in the order of several thousand crowns.
Occasionally, information appears saying that the success rate of KET is lower than that of fresh embryo transfer. However, this is not necessarily the case. The key factor is the correct procedure and method of freezing the embryo. It is crucial that the embryo at the clinic is frozen in the blastocyst phase, which it enters on about the fifth to sixth day after fertilisation of the egg with sperm.
Statistics show that more than 80% of embryos survive after freezing and thawing. As a result, FET may be more successful than fresh embryo transfer. In addition, with frozen embryo transfer, the patient is no longer stimulated as with a single normal IVF cycle. This provides better conditions for embryo nesting. Among other things, this is due to the fact that the patient is in a better mental and physical condition.
Rules of FET
One of the most common questions people ask about frozen embryo transfer is "what are the rules of FET". There is a very simple answer to his question. No strict measures are required. All you have to do is rest normally, avoid increased physical exertion and, ideally, not have sexual intercourse for a few days. There's no need to worry about the embryo leaving the uterus on its own. In FET, embryos are transferred together with culture fluid, which makes it easier for them to attach themselves to the uterine wall.
Frozen embryo transfer is a highly practical and effective method of IVF. If the embryos are frozen correctly, the chances of the egg nesting are very high. After thawing, the embryo undergoes a process known as convalescence, followed by transfer. It is very rare for an embryo not to survive thawing. At the same time, FET is a means of avoiding multiple egg sampling and the associated financial costs.
*This article is translated from Czech original to English language by translation agency Marvel, s. r. o.