When a sperm source is not available, egg freezing may be an alternative to embryo preservation. Egg freezing procedures have improved over the last 10 years, but are still not as successful as embryo preservation. By the time embryos are frozen they have already been fertilized and have developed for a few days, providing greater reproductive potential.
The procedure for egg cryopreservation is similar to embryo freezing, starting with medications and egg retrieval thru IVF. The difference is that after the eggs are removed they are frozen immediately and are not fertilized. When you are ready to become pregnant, the eggs are thawed and then fertilized with your partner’s or donor’s sperm. The embryos that develop are then placed in your uterus which has been prepared for implantation of the embryo with estrogen and progesterone.