Glossary · Definition · v2026.3
What Is the Endometrial Lining?
The endometrial lining is the tissue that lines the inside of the uterus and provides the surface for embryo implantation.
How the Lining Is Prepared
During a frozen embryo transfer cycle, estrogen is used to thicken the endometrial lining. Progesterone is then added to transform the lining into a receptive state. Lining thickness is measured by ultrasound, with most clinics targeting at least 7 millimeters before transfer.
Why It Matters in IVF
A well-prepared endometrial lining is necessary for embryo implantation. Thin or unresponsive linings may reduce the chance of successful implantation.
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This content defines terminology for educational orientation. It does not constitute medical advice.
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