Biopsy-free profiling of the uterine immune system in patients with recurrent pregnancy loss and unexplained infertility
Kilian Vomstein, Pia Egerup, Astrid Marie Kolte, Ida Behrendt-Møller, Amalie Dyhrberg Boje, Marie-Louise Mathilde Friis Bertelsen, Cecilie Sofie Eiken, Michelle Raupelyté Reiersen, Bettina Tóth, Nina la Cour Freiesleben, Henriette Svarre Nielsen
Abstract
RESEARCH QUESTION: What are the differences in menstrual blood lymphocytes between controls, patients with recurrent pregnancy loss (RPL) and patients with unexplained infertility (uINF)? DESIGN: Prospective study including 46 healthy controls, 28 RPL and 11 uINF patients. A feasibility study compared lymphocyte compositions of endometrial biopsies and menstrual blood collected during the first 48 h of menstruation in seven controls. In all patients, peripheral and menstrual blood from the first and subsequent 24 h were analysed separately by flow cytometry, focusing on the main lymphocyte populations and natural killer (NK) cell subsets. RESULTS: NK cell counts versus controls (11.42 ± 4.05%, P = 0.021; 12.86 ± 4.29%, P = 0.009 versus 8.4 ± 3.5%). CONCLUSIONS: Compared with controls, RPL and uINF patients had a different menstrual blood-NK-subtype profile, indicating an altered cytotoxicity. In future studies, this non-invasive analysis might enable identification and monitoring of patients receiving immunomodulatory medications.