Transfer of frozen thawed embryos from previous cycle can give the patient another chance of achieving a pregnancy without undergoing a full IVF cycle.

Embryos from an IVF cycle (where a transfer is medically not appropriate) can also be frozen so that the clinical problems can be corrected before transfer of embryos.

• Risk of OHSS
• Patient undergoing treatment for cancer

The embryos are transferred into the uterus after preparing the endometrial lining (lining of the uterus). As the embryos are already there, this cycle does not require stimulation of the ovaries or egg collection procedure.

Points to note:

• The FET cycle can be done any time after the initial treatment
• Approximately two thirds of the frozen embryos survive thawing.
• Not all cells in an embryo may survive.
• After thaw, the embryos can be cultured till they develop into blastocyst (D2/3- D5).
• The transfer is planned according to the grading of the embryos.
• Advantage of frozen cycle
• Provide patient with additional cycle of opportunity.
• Less costly than fresh cycle.
• Easier cycle control.
• Freezing embryos overcomes the negative effect of excessive hormonal changes in stimulated cycle on pregnancy outcome.
• Reduces risk of OHSS.