THE PRESENCE OF MAST-CELLS IN THE HUMAN ENDOMETRIUM PRE-INSERTION ANDPOSTINSERTION OF INTRAUTERINE-DEVICES

A study of the density of mast cells in the human endometrium was carr ied out on biopsy specimens prepared for light microscopy in 87 cases with three types of IUDs (stainless steel ring SS-type, copper Cu-T 22 0 and LNG-IUD levonorgestrel-releasing device) pre- and post-insertion . The results revealed that, in general, there was an increase of mast cells after 3 to 24 months' use of IUD, independent of type (p<0.01 w hen compared with the pre-insertion value). The increase in number of mast cells was most prominent in women having used the Cu-T220 IUD for 24 months (p<0.05 when compared with the SS-IUD and p<0.01 when compa red with the LNG-IUD). The difference between the SS-IUD and the LNG-I UD as to the number of mast cells was not significant. No significant difference was found between the ''bleeders'' and ''non-bleeders'' in any of the three types of IUDs. It is noteworthy that patients using t he Cu-T220-IUD had the highest percentage of patients with abnormal bl eeding (>50%) and that this group also had the highest density of mast cells per mm2 after 24 months' use. Although no significant differenc e with regard to the density of mast cells could be found between the ''bleeders'' and the ''non-bleeders'' in the present study, the number of ''bleeders'' of the three study groups is usually small and someti mes this number does not allow an adequate statistical analysis for co mparison. Further investigations, involving larger number of IUD users , may yield a better understanding with regard to the potential relati onship between the number of bleeding episodes and the density of mast cells in the human endometrium.