Day 3 vs Day 5 Embryo Transfer

For many years, embryos were transferred back into the uterus three days after the egg retrieval procedure. At this stage, the embryos are usually between 6-8 cells. With new advancements in the embryo culturing techniques, we are now able to grow the embryos for 5 to 6 days. This embryo is called a Blastocyst. There are many benefits to transferring embryos at this stage of development. A Day 5 embryo has a longer time in culture and any embryo that may have abnormalities or genetic defects may stop developing naturally on their own during this period. Thus, this self selection culture process allows the "healthier embryos" more time in culture to make the selection process of which embryo to be transferred back to the uterus a lot easier because one or two of the embryos may have grown a little faster than its sibling embryos, allowing it to be chosen for embryo transfer. This accounts for a high rate of pregnancy doing the embryo transfer on Day 5 versus Day 3. Additionally, Day 5 embryos have a high rate of being successfully frozen and transferred during a Frozen Embryo Transfer Cycle.

For patients who have only a couple of embryos to choose from, a Day 3 transfer may be appropriate. Dr Russell and our experienced IVF team will assist you every step of the way through your IVF process. If you have questions regarding the embryo transfer process or for any other concerns, please contact us.