Are Fresh Donor Embryos Better to Transfer to a Recipient Than (thawed) Warmed Donor Embryos?
Are We Forgetting About Fresh Vs. Frozen Eggs as the Source?
This is a follow-up from our latest blog concerning the two-step process of embryo creation, with or without preimplantation genetic testing (PGT), for polycystic ovary syndrome (PCOS) that requires vitrification. There is overwhelming evidence-based data in the existing literature that frozen embryo transfer (FET) provides a more favorable outcome than fresh transfers. By and large, this is with self (autologous) eggs.
Recently, a study was published in The Journal of the American Medical Association which looked at fresh embryo transfers from donor eggs compared to thawed embryos. The study showed an increase in delivery with fresh embryos which is in contradistinction to the above. One should note however that the study was a retrospective review (historical review which usually contains varying degrees of bias) of combined data from hundreds of programs using different criteria for donor selection and protocols. Furthermore, vitrification methods and lab skills vary by clinic.
The recipients in the study were all different. This means that a recipient would have either a fresh or frozen, but could not act as their own control, which is the ideal comparison. Furthermore, the data was collected from 2014 -2017 – a lot has changed in the technology of vitrification and PGT since then, making these comparisons potentially biased. It should be noted that the study is a good start for exploring the question of fresh versus frozen, especially in donor egg cycles.
Fresh cycles would be less expensive since it involves fewer lab procedures and time. Plus, it doesn’t include PGT, which adds cost. However, it automatically prevents recipients from using state-of-the-art next-generation sequencing for PGT, the results of which cannot be turned around in time to allow a fresh transfer. It is more complicated to coordinate recipient and donor cycles but this was the original way of doing said cycles 25 years ago so it can be done. The recipient still can have the same hormone replacement protocol whether fresh or frozen embryos are used – it’s all about the cycle coordination.
At CFNYC, we can perform both fresh and frozen donor egg cycles, and have time-tested experience in all aspects of reproductive care and assisted reproductive technology. Please explore our resumes and bios: Dr. Paul Gindoff / Dr. Beth Hartog.
At this time, we do recommend frozen embryos for donor cycles at CFNYC. The bigger question is whether frozen egg outcomes can rival fresh retrievals of donors with subsequent freezing of embryos and transfer, as compared to starting the treatment with frozen eggs from an egg bank. This study needs to be done and our inclination is that fresh retrieval is far superior.
When planning an egg donor cycle, make sure you discuss all these iterations and alternatives.
At CFNYC, we spend as much time with you as needed to customize your cycle and experience to optimize results. The doctors at CFNYC have decades of clinical experience, and lead academic programs and published research in these areas, in addition to being on editorial boards for years. They are at the cutting edge of best care practices.
Paul R. Gindoff, MD
Owner, Clinician at Chelsea Fertility NYC (CFNYC) in the City of New York, NY
Tenured Professor, GWU School of Medicine
Member of ASRM Editorial Board