In vitro fertilisation (IVF) is a process of fertilisation where an egg is combined with sperm outside the body, in vitro (“in glass”).[1]https://en.wikipedia.org/wiki/In_vitro_fertilisation IVF may be used to overcome female infertility when it is due to problems with the fallopian tubes, making in vivo fertilisation difficult. It can also assist in male infertility, in those cases where there is a defect in sperm quality; in such situations intracytoplasmic sperm injection (ICSI) may be used, where a sperm cell is injected directly into the egg cell. This is used when sperm has difficulty penetrating the egg. In these cases the partner’s or a donor’s sperm may be used. ICSI is also used when sperm numbers are very low. When indicated, the use of ICSI has been found to increase the success rates of IVF.
Approximately 3 days after fertilization, embryos are ready for transfer, but some patients prefer to wait a few days until they have reached the blastocyst stage (generally 5 days after fertilization).[2]https://blog.scrcivf.com/ivf-process-timelineThe embryo or blastocyst is instilled into the uterus via a thin, flexible plastic tube, which is gently passed through the opening in the cervix leading to the interior of the uterus. You will not need sedation for this procedure. It is generally painless but some women may experience mild cramping. You can watch the transfer as it happens with ultrasound technology.
According to NOVA IVF [3]https://www.novaivffertility.com/fertility-help/how-long-does-it-take-for-the-embryo-to-implant-in-the-uterus/, The fertilized eggs or human blastocysts normally hatch out of their shell and start to implant about 1 or 2 days after the 5th day of the IVF blastocyst transfer. This means the implantation takes place about 7 to 8 days after fertilization of the egg.