Description of the population and ultrastructure of cells on IUDs.

We looked at the cell population and individual cell ultrastructure in samples from the surfaces of removed IUDs. The women had worn the devices for 48 hours to eight years prior to removal. The layer of cells which covers IUDs two days after insertion was found to consist of macrophages and neutrophils. The macrophages were exceptionally active, but fragments of sperm were observed in their phagosomes only rarely. All observed free sperm were degenerated. The fibrous tissue which was formed on IUDs later contained numerous lymphoid cells.