Reproductive healthLecture
Endometrial receptivity: from biosensor to clinical practice
Receptive or non-receptive? A continuum-based view of the endometrium as an active biosensor that selects against poor-quality embryos. Why the classical 'all in the egg' narrative misses recurrent implantation failure — and how a new diagnostic toolbox is taking shape.
Audio: MultiSubtitles: EN · UA · RU39 min
Nick Macklon
Professor, MD, PhD
Professor and Medical Director of the London Women's Clinic and Co-Chief Editor of Reproductive BioMedicine Online. Internationally recognized for his research on ovarian stimulation, endometrial receptivity and periconception. Author of more than 200 scientific papers.
London, United KingdomLinkedIn →
What was shown
A challenge to the 'all in the egg' narrative built around the Pirtea / Atta papers that reported up to 95% cumulative pregnancy with serial euploid transfers. The talk reframes endometrial receptivity as a continuum rather than a binary on/off, and introduces the biosensor concept: stromal cells migrate towards good-quality embryos and stay back from poor-quality ones.
Key findings
In a Rotterdam high-resolution cytogenetic study, 82% of normally developing blastocysts labelled euploid by commercial tests carried some mosaicism. In vitro, decidualised stromal cells migrate to engage with good blastocysts and remain static around poor ones. In endometrium from women with recurrent miscarriage, this discrimination is lost — stromal cells engage with poor embryos too, allowing implantations that should not have happened. The 95% cumulative figure of Pirtea / Atta is biased by serial drop-out and does not generalise to the typical RIF clinic.
