The transfer of embryos into the uterine cavity is one of the links in the process of in vitro fertilization. The main issue remains the optimal age of the embryo for transference. Until recently, it was believed that the ideal embryo, reached the stage of fragmentation, that is, when the embryo is 2-3 days old. But, as we already know, with natural conception the embryo gets into the uterus only on the 5th day. In this regard, we will consider the expediency of embryo transfer on the 5th day.
Pros and cons of embryo replenishment on day 5
The embryo, reaching the age of 5 days, already has about 30-60 cells, so they are more durable and have a higher potential for implantation into the endometrial mucosa. It is noted that the percentage of successful pregnancies is much greater, namely, when carrying a five-day embryo. It is known that embryos at the stage of fragmentation can carry genetic defects in themselves in about 60% of cases, and in the blastocyst stage only in 30% of cases, since the majority of "defective" embryos do not survive to 5 days. Therefore, the probability to select more successful embryos and increase the chance of getting a pregnancy is much higher if you use the human embryo in the blastocyst stage. The disadvantage of this method is the separate development of the embryo and endometrial mucosa up to 5 days, which may be the reason for stopping the division of embryos.
Embryo Embryo Transfer Procedure on Day 5
The very procedure of embryo transfer at the stage of blastocyst is identical to that on days 2 and 3. A woman who is on a gynecological chair is injected with a sterile thin catheter into the uterine cavity through the cervical canal, and embryos are inserted through the catheter. Usually, 2 embryos are planted to avoid multiple pregnancies.
Thus, we see that the embryo embedding on the blastocyst stage gives higher chances of obtaining the desired pregnancy.