[Further electron microscopy studies on early development of endocervical epithelium in human fetuses]

Electron microscopical investigations of the cylindrical epithelium of the human cervix uteri demonstrate in the cytoplasm of the secretory cells tubular precoursers of secretory granules which become granular during the differentiation process of the epithelium. In the seventh fetal month mucous granules occasionally show a confluence. In the eights fetal month, typical cuboidal reserve cells are detected near the basis of the epithelium between the secretory cells and the ciliar cells. Under maximal increase of the rough endoplasmatical reticulum the production of secretory granules proceeds. By mitosis a functional adaptation of the epithelium to the growth of the cervical canal is achieved. The differentiation of the endocervical epithelium is nearly finished in the middle of the ninth month. At this time, merocrine extrusion processes become evident.