In a perfectly normal conception, on the 6th or 7th day, the fetus, surrounded by a transparent zone, leaves this protected environment in which it lived until that time and is implanted in an environment that is waiting to be friendly, inside the endometrium. . The moment of implantation is called hatching.
But when we do not have a normal conception, but an extracorporeal effort that we want to lead to conception, then the hatching is also helped.
In the IVF, the outer transparent zone is either hard or thick, with the result that the fetus can not split it and find its place in the uterus so that it can be implanted and thus begin its intrauterine life, the beginning of a pregnancy.
If the transparent film is thick or hard, hatching is impossible. This is why it is assisted in the case of in vitro fertilization.
The method is applied to the embryos before the embryo transfer, in order to ensure as many chances as possible for a good implant and of course pregnancy.
The transparent zone can be hardened or thickened by prolonged culture in the laboratory, or by freezing the embryos or by cryopreservation.
Assisted hatching is applied when the woman is over 37 years old, or when the quality and quantity of eggs dictate it. That is, when the follicle-stimulating hormone, on the third day, is quite high.
It also applies when embryos from in vitro fertilization are of poor quality, or are developing very slowly, or have slow cell division.
The method is indicated when there are failed IVF attempts, more than one cycle per pair.
It is true that assisted hatching helps a lot and increases the rates of pregnancy and childbirth.
Assisted hatching is as follows:
The embryo is held in place with a fine needle and an acidic solution is extracted from the membrane.
The hatching is achieved either by thinning the outer transparent zone, or by making a small hole. In this way, the work of the fetus is facilitated.
The embryo is then rinsed and placed back in the culture, in the special oven.
Once this movement is made, the embryo transfer takes place very quickly. These movements must be done immediately and mediate the interval between egg retrieval and embryo transfer.
Even the word testifies to it. An egg is obtained and an embryo is implanted.
Success depends on the method of hatching that will be followed.
All effort must be made before the fetus is implanted in the woman’s uterus.
The goal is to thin the transparent zone so that the fetus can easily come out and attach to the implant in the uterus.
Many times, the transparent zone is thick or hard, especially if the fetuses come from older women, with the result that the fetus does not find its way to the hospitable embrace of the uterus.
The hole, or thinning, facilitates this effort of the fetus.
Assisted hatching takes place only when the embryologist deems it necessary, who controls the eggs and their development.
The thinning or the hole is done with a very thin laser or with mechanical friction.
The procedure is repeated for each fetus separately.
The endometrium may be suitable in thickness or quality, but if the fetus does not break the transparent band to attach to it, then pregnancy is not achieved.
It is true that during embryo transfer, all these parameters have been adjusted to ensure all the conditions for the coveted pregnancy.
In normal conception these are facts. In IVF, however, all parameters are technically guaranteed.