Why aren’t all embryos obtained from an IVF cycle suitable for freezing?

Today, in In Vitro Fertilization treatments, it is not extraordinary to find ourselves on the day of embryo transfer with a high number of good quality embryos. For a fresh transfer we shall be electing the embryo or embryos that morphologically and kinetically demonstrate greater development and ‘the other’ good quality ones can be cryopreserved.

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