[Investigation on endometrium from menstrual blood as a source of non-invasive tissue].

To investigate the feasibility of a non-invasive sampling method by collecting menstrual blood and obtaining endometrium for further research in menstruation-related diseases. On the second day of menstruation, menstrual blood was collected with menstrual cups for 4 hours, and the menstrual endometrium was filtered through a metal screen for weighing, cryopreserved, immunohistochemical staining and cell culture. The collection process was painless and non-invasive. In the control group, the menstrual volume was (9.1±0.7) ml, and the endometrial tissue weight was (91.0±14.7) g. In the endometriosis group, the menstrual volume was (9.6±1.9) ml (0.022), and the endometrial tissue weight was (134.7±43.9) g (0.057). Endometrial cell culture was successful in all patients and should not be contaminated. The growth curve was a finite cell line type. The expression of cytokeratin 19 and vimentin in menstrual endometrium and cells were positive. By collecting menstrual blood and filtering endometrial tissue, it is an ideal non-invasive sampling method. In combination with advanced experimental technology, menstrual endometrium make further researches of endometriosis, endometrial lesions or other menstruation-related diseases possible.