Round tubular glands with frequent mitotic figures - glands are viewed en face in this section.
Now, the same glands are viewed longitudially - slight coiling is seen.
Yet another example of proliferation glands with pseudostratification and mitotic figures.
In response to estrogen, endometrial glands proliferate. The endometrial glands exhibit a characteristic histology such as: (1) glandular architecture is round or tubular; (2) the lining cells are pseudostratified with dark nuclei; (3) numerous mitotic figures are found toward the luminal side of the glands; (4) the stroma can range from edematous, spindled to predecidualized.
Unlike secretory endometrium, it is not useful or clinically relevant to date proliferative endometrium.
1 Nucci MR, Oliva Esther. Gynecologic Pathology: Foundations in Diagnostic Pathology. Philadelphia, PA: Elsevier: 2009: 199-200.