The cells from intrauterine contraceptive devices: with special reference to the occurrence of mast cells.

A study of cytologic smears from 26 women using intrauterine contraceptive devices (IUDs) confirmed our previous findings for mast cells and further defined the averages, proportions and types of cells in IUD smears. The average number of cells was found to be 65.5 x 10(4), with a range of 1.3 x 10(4) to 280 x 10(4). The cellular proportions found were 49.0% macrophages, 42.7% polymorphonuclear leukocytes, 4.0% endometrial glandular cells, 1.3% mast cells and 3.0% other cells. Total nucleated-cell counts showed one group with a large number of cells (greater than 5 x 10(5) cells) and another group with a smaller number of cells (less than or equal to 5 x 10(5) cells). These groups showed significant differences in cell types, with a predominance of polymorphonuclear leukocytes in the former and macrophages in the latter. The mast cell counts were similar in both groups. The data suggest that mast cells have a role in IUD functioning. It may be based on an immunologic mechanism.