Day 5 vs. Day 3 Embryo Transfer

Day 5 embryo transfer vs. Day 3 embryo transfer vs. “Sorry, no transfer; all of your embryos arrested”.

Has this ever happened to you ? Your entire IVF/ICSI cycle “wasted” because you made few embryos that did not survive in the laboratory to become blastocysts (day 5 embryos) so you did not have an embryo transfer at all ? I have seen several couples who have had this happen to them, and feel our patients need to have this issue addressed.

For many decades, women have conceived and delivered healthy children after embryos were transferred on day 3 after egg retrieval. As laboratory and culture systems improved, it became possible to culture embryos in the laboratory for a couple of more days. Not all embryos can survive in a laboratory this long, although they can result in normal pregnancies if transferred on day 3 of laboratory development. The advantage of a day 5 or blastocyst transfer is a higher implantation and pregnancy rate per embryo transferred since less “strong” embryos will not survive, and therefore the scientists and physicians are stressing all of the embryos to detect the best quality embryos and also decrease the chance of multiples such as twins, by transferring fewer embryos. This method of embryo selection is most helpful in women with so many embryos to choose from that the embryologists can’t estimate which are the strongest on day 3 after retrieval, so they observe their development for a few more days. This method does not improve the chance of pregnancy from any individual embryo, it only finds the strongest that survive. If a patient only has 2 or 3 embryos, prolonged culture does not improve their quality, and the best chance for pregnancy is therefore an earlier transfer on day 3.

Also, some couples have been told that normal embryos will develop to blastocysts in the lab, and if all of their embryos died it was “meant to be” implying that their embryos were not normal and they either would not conceive at all or would miscarry an abnormal fetus; a cheaper way of assessing the genetic health of an embryo. There is absolutely no scientific evidence for these opinions.

At IRMS, we do both day 3 and day 5 embryo transfers. Our recommendations are individualized for each couple and not a “one size fits all” approach, as we attempt to attain the highest chance for a term, healthy live birth for each couple.

Bottom line:

  1. Transferring 1 day 5 embryo (blastocyst) has almost the same pregnancy rate as transferring 2 day 3 embryos, and almost no chance of twins (compared to a 20% chance of twins transferring 2 day 3 embryos).
  2. Transferring 2 day 5 embryos has a higher pregnancy rate and a 30 to 40% chance of twins
  3. Some patients are better served having a day 3 embryo transfer.

I recommend all couples have the discussion with their Doctor about the transfer philosophy at their program, long before the sad phone call on day 5 that their transfer is cancelled due to the “arrest” of all of their embryos.

For more info or book an appointment with my team or another practice doctor contact us online, via our social media channels or give us a call at 973.548.9900.

Margaret Graf Garrisi, MD joined the Institute for Reproductive Medicine and Science in 1999. Dr. Garrisi brings more than 30 years of experience and achievement in Obstetrics, Gynecology and Infertility to her position as Medical Director of Assisted Reproduction in the Division of Reproductive Endocrinology.


  1. Hi – this is such an important discussion especially given some clinics’ robotic policy of insisting on pushing them to day 6 or 7!!! What is the chance that a day 3 embryo that would have arrested on day 5 in vitro would have a better shot in utero?

    1. Hi-thank you for your very detailed question. We are one of the few practices that watches embryos from the moment of fertilization
      and evaluate progress to see if a Day 3 transfer is indicated. Certainly prior to our ability to grow embryos out in the Lab beyond Day 3 all
      embryo transfers were on Day 3 and tens of thousands of IVF babies were born. While we still know now that Day 5 or Day 6 embryo transfers are more ideal
      Day 3 embryos do make babies.

    2. My sister just went through a very disappointing IVF round. She has 6 live embryos that arrested at day 5, literally hours before transfer. All 6 of them, even though they were developing perfectly at cleavage and morula stages… She is devastated and cannot help but wonder if some of them would have survived if she had a day 3 transfer..

      1. We are so incredibly sorry for her loss and yours as well. Thank you for sharing your thoughts with us and please let us know if we can be of any assistance at all.
        Though it seems to be a bit contradictory to the science of today, we still believe there are some embryos that just do better in the human body sooner rather than to remain in culture longer.

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