Endometrial receptivity refers to the state of the endometrium when it is optimally prepared to accept and support an embryo for implantation. This phase typically occurs during a specific period known as the “window of implantation,” which happens about 5 to 6 days after ovulation in a typical menstrual cycle (Lessey 2011). During this time, the endometrium undergoes decidualization which involves cellular and molecular changes to improve its ability to interact with an embryo (Okada 2018):
- Specialized cells secrete factors to promote implantation
- Immune cells accumulate to develop embryo tolerance (to prevent rejection) and to provide factors to support implantation
- Re-modelling of blood vessels occur in anticipation for the growing fetus
Synonyms:
receptivity, receptive, decidua, decidualization, window of implantation, implantation window