THE FINE STRUCTURE OF THE HUMAN ENDOMETRIAL CILIATED CELL

Sixty-eight histologically normal specimens from all stages of the menstrual cycle were examined during an ultrastructural study of the human endometrial ciliated cell. The 'clear' ciliated cells found initially were seen to become at first dense and then secretory. These changes are advanced as an explanation to account for the previously observed reduction in frequency of the ciliated cell during the luteal phase. The possibility of an hormonal control mechanism is discussed.