For some couples undergoing IVF, one of the most significant ethical issues they may face is the fate of the surplus embryos.
Following embryo transfer, any remaining viable embryos are then cryopreserved (frozen) for later transfer. Not all embryos are suitable for freezing. The embryos can be frozen at the pronucleate, early cleavage or blastocyst stage. Overall about 50% of frozen embryos survive the thawing process. In the United Kingdom, the embryos can be frozen for up to 10 years with the intent of thawing and transferring them at a later …

Conventional or standard IVF treatment involves the administration of fertility drugs, monitoring of the cycle, collection of eggs, mixing eggs and sperm together outside the woman’s body in a culture dish or test-tube. Any resulting embryos are left to grow and the best 2-3 embryos are then transferred into the woman’s womb. Any remaining embryos of good quality may then be frozen for future use. In the United Kingdom a maximum of three embryos are replaced.
IVF cycle. The diagram below summarises the IVF cycle.

The original indication for IVF was tubal …