With IVF or ICSI treatment, patients often have multiple quality embryos created from one treatment cycle. The good-quality embryos that cannot be used in that cycle may be frozen and stored for future use.
Today, in most clinics, embryo freezing is one of the very routine services offered as part of fertility treatment. Frozen embryo transfers have allowed many patients to achieve more than one pregnancy from a single treatment cycle and have also prevented multiple pregnancies.
Embryos tolerate the freezing and thawing process very well with a survival rate greater than 90%. The pregnancy rates with frozen/thawed embryos have been proven as good as fresh embryos. Embryos can be frozen at any stage of development during treatment; however, our clinic most commonly freezes embryos on Day 5 or Day 6 of development.