The presence of mast cells in the human endometrium pre- and post-insertion of intrauterine devices

Abstract

A study of the density of mast cells in the human endometrium was carried out on biopsy specimens prepared for light microscopy in 87 cases with three types of IUDs (stainless steel ring SS-type, copper Cu-T 220 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 when 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 compared with the LNG-IUD). The difference between the SS-IUD and the LNG-IUD 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 the Cu-T220-IUD had the highest percentage of patients with abnormal bleeding (> 50%) and that this group also had the highest density of mast cells per mm2 after 24 months' use. Although no significant difference 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 sometimes this number does not allow an adequate statistical analysis for comparison. Further investigations, involving larger number of IUD users, may yield a better understanding with regard to the potential relationship between the number of bleeding episodes and the density of mast cells in the human endometrium.