In the IVF research facility, after the egg retrieval, treatment is completed by IVF (In-vitro preparation) or by ICSI (intracytoplasmic sperm infusion) and the subsequent embryos are put in an incubator for an additional turn of events. The phases of development are as per the following:
- The day of egg retrieval is considered as Day 0 (IVF or ICSI is done after egg retrieval).
- The pronuclear stage on day 1 (embryologist checks as to how many eggs have successfully fertilised).
- The two to four-cell stage on Day 2.
- The eight-cell stage on day 3.
- The morula stage on day 4.
- The blastocyst stage on day 5 or day 6.
The blastocyst contains two distinctive cell types-the internal cell mass which forms into the fetus, and an external layer of cells called trophectoderm which forms into the placenta.
Earlier, embryos transfer following IVF or ICSI has been completed on Day 2 or Day 3 after egg collection. Be that as it may, progresses in the IVF research centre advances permit us to now culture embryos for five or six days. This gives the embryos a greater chance to prove their development potential. A few embryos quit developing (capture) prior to 5/6 day. This 'natural selection' enables the embryologist to recognize and pick the best-embryo/s for embryo transfer.
Advantages of Blastocyst Culture
The human body is the best incubator for human embryos but if there are several embryos to choose from on day 3, we know that not all will survive to day 5 whether they are in the laboratory or the womb. Keeping the embryos in the laboratory for these two extra days eliminates the possibility of transferring a (healthy-looking) embryo on day 3 which would naturally perish before day 5. Therefore it gives a better chance of transferring an embryo which will lead to a successful pregnancy and birth.
The decision to choose a day 3 or day 5 embryo transfer will depend on the circumstances at the time. The embryologist will fully discuss this with the patient. We believe it is correct to proceed to day 5 wherever possible and do not believe that finance should play a part in this decision. Therefore, since summer 2017, Concept Fertility does not charge for blastocyst culture and transfer.