Role of Bacterial and Viral Infections and Co-Infections in Miscarriages

Abstract

Abstract Aim To investigate the potential role of the following bacterial/viral panel (Chlamydia trachomatis, Ureaplasma urealyticum/parvum, Mycomplasma hominis/genitalium, Gardnerella vaginalis, HSV1/2, EBV, CMV, VZV, HHV6, HHV7, HHV8) as causative factors for miscarriages in women by testing endometrial biopsies. Anaerobic and aerobic microorganisms causing dysbiosis and endometrial bacterial colonization by unbalanced growth were additionally tested. Materials and methods In total, 65 patients with a history of early and late miscarriages were analyzed. DNA extractions, real-time qPCR, agarose gel-electrophoresis were applied. Comparative analysis of the current with previously obtained data on the described panel in menstrual tissue samples was performed. Results In 64,6% of all tested endometrial biopsies bacterial and/or viral pathogens were detected. In 49,23% of all tested samples we found bacterial, while in 15,3% – viral pathogens. These results are similar to our previous data on menstrual tissue samples of infertile women – 61,1% infected, as 48,8% had bacterial and 22,2% had viral pathogens. Gardnerella vaginalis and Ureaplasma parvum were detected in 31,25% and 3,12% of all bacterial infected endometrial biopsies, significantly lower in comparison to the estimated rate of 69,31% and 61,36% on menstrual tissue. Anaerobic and aerobic dysbiosis were detected in 53,33% and 27% of the bacterial infected endometrial samples. In 13,33% a dysbiosis with a mixed etiology was found, while in 7% a dysbiotic condition with a totally absent findings of targeted bacteria and Lactobacillus was observed. EBV, CMV, HHV6 and HHV7 were detected in 30%, 30%, 20% and 20% of the positive for viral factors endometrial biopsies and in 40%, 7,5%, 10% and 42,5% in menstrual tissue samples. In the current study 62,5% bacterial co-infection and 12,5% bacterial/viral co-infection variants were found. Infections with the rest of the target pathogens were not detected in the endometrial biopsies. In contrast to the endometrial biopsy results, Mycomplasma hominis, Ureaplasma urealyticum and HSV2 were detected in our previous research on menstrual tissue samples. Conclusions Our research suggests a possible dysbiosis as a consequence of bacterial/viral endometrial colonization, associated with miscarriages. We prove that menstrual tissue, containing parts of the functional endometrial layer, is a reliable and accurate noninvasive sample for infectious screening of the upper genital tract.