Chances of success

A blood test 12 to 14 days after the embryo transfer shows if pregnancy was achieved. What you need to know :

1) Relationship between follicle and egg cells:
Basis for the treatment is the amount of follicles that developed through a controlled stimulation of the ovaries. An egg cell cannot be obtained from every follicle. During puncture not the follicle is retrieved from the body, but a liquid is extracted from said follicle with the aid of a needle. If, for example, 16 follicles developed, approximately 12 egg cells can be obtained. Please note that this number is subject to individual fluctuation.

2) Relationship between extracted and mature egg cells: Egg cells must achieve distinctive phases of development in order to be ready for extraction. While these phases are achieved by most egg cells, some will not succeed. For example: 10 out of 12 egg cells are mature, in other words, have reached metaphase II.

3) Relationship between mature and fertilized egg cells: Although egg cells in a mature state fulfill all the requirements, still not all of them are fertilized the day after. This applies to both IVF and ICSI. It might be the case that only 8 out of 10 egg cells can be fertilized.

4) Relationship between fertilized egg cells and embryos with a regular development: The further development of fertilized egg cells differs strongly. Not every embryo divides in a timely and regular manner. In such cases it is possible that just 5 out of 8 embryos reach the blastocyst phase by day 5. All remaining embryos may show signs of an incomplete development insufficient for day 5.

5) Relationship between embryonic development and the possibility of cryopreservation:
After two embryos in their blastocyst phase have been transferred, three embryos in their blastocyst phase remain for cryopreservation. The last three left are not suited for this procedure.