Page 76 - PRECONGRESS COURSE 04

Gene expression in the pregnant endometrium is influenced by embryonic phenotype
Endometrial gene expression signature
Tissue implanted with cloned bovine conceptuses from single cell nuclear transfer (associated with high rates of placental abnormality)
differs from
tissue implanted with embryos conceived after fertilisation in vitro or by donor insemination.
Bauersachs et al The endometrium responds differently to cloned versus fertilized embryos. Proc Natl Acad Sci USA 2009; 106: 5681–5686. PMID 19307558.
Mansouri‐Attia et al. Endometrium as an early sensor of in vitro embryo manipulation technologies. Proc Natl Acad Sci USA 2009; 106: 5687–5692. PMID 19297625
Receptivity redefined
• Endometrialreceptivityisnotastaticstatein which the tissue is poised, awaiting the arrival of an adequately developed embryo.
• Anintegrativedefinitionofreceptivitymust embrace communication between maternal and embryonic cells.
• At‘receptivity’negotiationbeginsbetween endometrium and embryo.
• This may or may not lead to successful implantation, placentation, development and growth of a viable conceptus.
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