The re-epithelization of endometrium after menstrual desquamation.

MATERIALS

Human uteri were removed by vaginal hysterectomy on the first, second and sixth day of the menstrual cycle.

METHOD

Washing, pinning, fixation in glutaraldehyde 2.5%, dehydration in ascending concentration of ethanol, critical point drying with carbon dioxide, sputter coating with gold.

RESULTS

The re-epithelization of the endometrium starts immediatley after the onset of menstrual bleeding due to desquamation of the premenstrual endometrium. The remaining stumps of endometrial glands after the endometrial break-down, proliferate rapidly, forming marginal collars. Up to the sixth day the proliferative process has produced a continuous layer of fusiform cuboideal epithelial cells, which cover the entire endometrial surface of the uterine cavity. The dynamics of epithelial growth can be "seen" in following three subsequent stages of the process and in analyzing the arrangement of the cells around the openings of the endometrial glands. Accordingly ciliogenesis occurs in some surface endometrial cells. The paper gives an inconographic survey of the early proliferative phase, illustrating changes from glandular epithelium to the lining epithelial layer and ciliogenesis in the latter. The new formation of ciliae in endometrial epithelial cells is an unique phenomenon, being influenced by the cyclic endocrine regulation of the endometrial function in human reproduction.