Enzyme cytochemical studies of the mononuclear phagocytic cells in human uterine fluid.

Mononuclear phagocytic cells were present in normal uterine fluid. All transitional forms between monocytes and mature macrophages could be distinguished. The content of lysosomal enzymes in these cells was found to be identical to that of blood monocytes, which validates the hypothesis of their origin. Mononuclear phagocytic cells were more numerous in the uterine fluid aspirated from women with an intrauterine device (IUD). Furthermore, the activity levels of lysosomal enzymes in these cells were higher in the group of IUD users than in the nonusers, indicating a higher phagocytic activity of such cells in the IUD group, possibly secondary to the inflammatory process.