Is your provider’s documentation up to the challenge of these anatomy-based codes? Specificity is the keyword when coding endometriosis using ICD-10-CM 2023. You’ll need to know the location and sometimes whether the endometriosis is deep or superficial to select the most appropriate code. The table below will help you get up to speed on the remarkable number of new endometriosis codes, effective Oct. 1, 2022. Term tip: Endometriosis is a condition in which tissue similar to the lining (endometrium) of the inside of the uterus grows outside of the uterus.