- The newer vitrification method for IVF embryo freezing is becoming a more widely used technology.In our clinic vitrification of “spare” embryos after IVF is showing much higher “post-thaw survival” and pregnancy success rates after transfer.
How are frozen-thawed embryo transfer cycles managed?
At SWH, we use hormone replacement cycles because they have better success rates.
We have a live birth rate of over 50% per transfer procedure in women under 35 for frozen-thawed transfer cycles.
Blastocyst implantation in an FET cycle
Embryo implantation after frozen blastocyst transfers (FET) can be slightly delayed compared to that seen with fresh blastocyst transfer. This is sometimes referred to as “late implantation”, or delayed implantation.
However, the embryo implantation process is not different enough to warrant changing the timing of the blood pregnancy test. Frozen blastocyst transfers should have hatching and the beginning of implantation by about 1-3 days after the FET.
Early pregnancy detection following blastocyst transfer is possible with a sensitive blood assay for HCG hormone by about 9 days after a fresh or frozen blastocyst transfer.