The Milan Debate

The Embryology Lab at Pacific Fertility Center has a world-wide reputation as a provider of top quality embryology services. PFC is recognized as an innovator in the best methods to help build families, one healthy baby at a time. Visitors from around the world come to learn the skills our embryologists have developed. We welcome the opportunity to share what we have learned.

Last year, following a visit from 2 Italian embryologists I was invited to participate in a meeting in Milan on the subject of recurrent implantation failure (RIF). Specifically, this covers those patients that have had 3 or more failed IVF cycles and/or 10 or more embryos transferred to their uterus without pregnancy.

The meeting was very thorough, covering clinical (endometrium, cycle stimulation, luteal support, lifestyle, genetic and immunologic testing and empirical therapies) and laboratory (oocyte, sperm, embryo, genetics and embryo freezing) topics in short focused talks, given by experts mostly from Europe and 2 of us from the US. 550 physicians and embryologists attended the meeting from a total of 54 countries.

On the second and final day of the meeting I participated in a debate on Assisted Hatching (AH), a technique that makes a small hole in the non-living shell around the embryo with the aim of helping the embryo to hatch from its shell at the time of implantation. This is a technique that has been around for almost 30 years, but one that is used mostly in the US, with little adoption in Europe. In theory, a healthy embryo should be able to burst through this shell as this is a natural process for embryos. We believe that there are also enzymes produced by the uterus, and perhaps by the embryo too, that aid in thinning or dissolution of the shell as the embryo reaches the blastocyst stage and is ready to invade the endometrium.

My job was to argue for the motion that AH has a role in RIF patients, and my opponent was the very formidable Professor Simon Fishel from the UK (https://www.carefertility.com/support/ask-simon-fishel/) who argued against.

The audience was polled before the debate started, and although we were not shown the survey results at that time, I knew that the number on my side would be low as attitudes in Europe are very conservative and the technique is little used there. After a cordial handshake, I was to speak first and I argued that AH has very specific but important uses in IVF and that it is a valuable procedure for patients with multiple IVF failures.

We now know that freezing of any type causes an artificial hardening of the shell around the embryo. PFC mostly transfers a single embryo, so we freeze lots of embryos. I showed several videos showing that embryos really struggled, or in some cases even failed to hatch from hardened shells after freezing and thawing.

I conceded that AH appears to have little value with fresh embryo transfers since dozens of studies have failed to come to a consensus on this, and while most of them show some small improvement in clinical pregnancy rate after the use of AH, none show conclusively that AH improves live birth rates. Professor Fishel focused on these studies in his elegant and well-structured presentation, and really drove home the lack of support for AH in the scientific literature. However, he was unable to dispute the issue of hardening of the shell after freezing and we agreed that this now is a new application of the technique that needs further scrutiny and study.

We had a final handshake and some friendly words before the moderators closed the session and the audience broke for a coffee break where the topic was enthusiastically discussed some more.

- Joe Conaghan, PhD
PFC Lab Director

Photo Credits: EXCEMED

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