Glycogen Intermediate squamous cells are characterized by the presence of intracytoplasmic glycogen. The glycogenic deposits express the cellular differentiation. They are abundant in the post-ovulatory phase, during pregnancy (navicular cells) and in some menopausal smears. With Papanicolaou staining, glycogen gives a yellowish colour to cytoplasm which appear fissurated. In histological sections glycogen is visualized by PAS staining. (see also: Schiller test)