The ultrastructural morphology of epidermal keratinocytes, which at the end of pregnancy and after shedding of vernix represent the majority of amniotic fluid cell population, is analysed by electron microscopy. Special attention is focused on the morphological characteristics of epidermal keratinization according the changes of the cell's ultrastructure during this process: The transformation of the cytoplasma into keratin, the formation of the typical cell membrane of the keratinized squamous cells, and the findings concerning the intercellular space, especially of the zones of intercellular contact - desmosomes - and their changes.