Can my embryos be biopsied for CCS if they do not reach blastocyst stage by day 5?
In order to perform CCS, it is necessary for embryos to reach blastocyst stage. However, embryos may sometimes take longer to reach that stage. In such cases, embryos are cultured an extra day to give them another chance to reach it. If they do, biopsy is performed on day 6 without further consequences. Our only concern should be to cryopreserve and transfer them in a later cycle, since the maximum amount of time to culture them in vitro has already been spent. Therefore, embryos that reach that stage on day 6 can surely be tested by CCS.