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Updated: Jul 11, 2026

Isolation of Uterine Innate Lymphoid Cells for Analysis by Flow Cytometry
Published on: October 14, 2021
Endometrial lymphomyeloid cells in abnormal uterine bleeding due to levonorgestrel (Norplant)
1McMaster University, Faculty of Health Sciences, Department of Medicine, Hamilton, Ontario, Canada.
Abstract:
Endometrial lymphomyeloid cell subsets were evaluated in samples from normal women and from women with abnormal uterine bleeding due to subcutaneous levonorgestrel implants (Norplant) or an intrauterine device (IUD). The frequency of CD3(+), CD68(+), CD43(+) and endometrial granulated lymphoid cells was evaluated by immunohistochemical or phloxine-tartrazine staining of formalin-fixed paraffin-embedded samples. In normal women, cyclic variation in lymphomyeloid subsets was seen. In women using Norplant for contraception, the frequency of CD3(+), CD68(+) and CD43(+) cells was dramatically decreased, compatible with endometrial atrophy. When Norplant users with abnormal bleeding were compared to women without bleeding, however, the number of CD68(+) cells was significantly increased and the number of CD3(+) and CD43(+) cells was preserved, contrary to the hypothesis that this group would show a greater degree of atrophy and hence, tissue fragility. A similar pattern was seen in a preliminary study of women with bleeding associated with use of copper-only IUD contraception, and in samples taken from late secretory and menstrual biopsies from normal cycling women. Whether these changes in endometrial lymphomyeloid cells represent a result of bleeding arising from a common mechanism or rather cause the uterine bleeding is discussed.
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