A frozen embryo transfer (FET) is a reproductive technology used to transfer frozen embryos from the previous IVF cycle to use them in the next one. Unlike the regular IVF treatment when embryos are transferred back during the same ovulation cycle, with FET they’re frozen until the next one.
This can be done with the use of both the woman’s own eggs and donor’s eggs. The process of frozen embryo transfer aims to help women to recover from their previous IVF cycle and remove the desynchronization effect.
Both fresh and cryopreserved eggs work well with IVF, but the use of cryopreserved ones allows to choose the best of them and postpone the process of implantation if needed.
For better chances of success — when the transfer results in a healthy pregnancy, doctors of fertility agency “Parens Fertility” in Lviv recommend freezing a few eggs whether they carry your own genetic material or donor’s.
When can FET be recommended?
During the ovarian stimulation process, ovaries form a few eggs for further insemination. Usually these eggs can result in healthy embryos, but only 1-2 of them can be implanted in the uterus in fresh condition. The rest of them can be successfully frozen in case a pregnancy didn’t start with the use of fresh eggs or if a woman plans another IVF pregnancy later in future.
The better solution is to freeze all the embryos and not to implant them immediately in the non-suitable stage of the uterus development — this is a major risk of ovarian hyper-stimulation syndrome. Also, the pregnancy has more chances of success if the patient’s eggs are frozen in clinic until a later ovulation cycle — until the uterus has a more natural environment for that.
Postponing a pregnancy is another recommendation for the use of FET. In their 30s or 40s women have less chances to conceive a child in a natural way because of a lesser number of eggs in ovaries.
Success rates of FET
There are many factors that affect pregnancy success rates. Age is possibly the most important one of them. Eggs taken from women younger than 30 and frozen through vitrification during the blastocyst stage have 90% of survival through the thawing process.
This is why vitrification aka instant freezing has the same success rate as a fresh embryo — genetic material and cell walls are less likely to be damaged by the process.
Does it work with IVF?
Freezing an embryo for its delayed transfer is really helpful during the IVF treatment — this way hormones have some time to synchronize cycles and prepare the uterus for a successful embryo implantation.
IVF in general is a stress to a woman’s body. Therefore, doctors recommend giving it some time to stabilize while embryos are going through freezing, testing and thawing stages.
To learn more about modern fertility technologies, their risks and chances of success, contact agency “Parens Fertility”:
Phone: Ukraine +38 067 510 82 35, Poland +4 812 333 74 77
Address: Lviv, 36 Shchyretska St.