Microbiota of semen samples with normozoospermia: analysis of real-time PCR data

About authors

1 Ural State Medical University, Yekaterinburg, Russia

2 Medical Center “Garmonia”, Yekaterinburg, Russia

3 Yeltsin Ural Federal University, Yekaterinburg, Russia

4 Institute of Mathematics and Mechanics, Yekaterinburg, Russia

5 Ivanovo State Medical Academy, Ivanovo, Russia

Correspondence should be addressed: Ekaterina S. Voroshilina
Repina, 3, Yekaterinburg, 620014; moc.liamg@anilihsorov

About paper

Acknowledgments: the authors would like to thank VN Khayutin, director of “Garmonia” Medical Center, for allowing them to conduct the study in the clinic's laboratory department.

Author contribution: Voroshilina ES — organization of the study, data analysis, writing the article; Zornikov DL — data analysis, writing the article; Ivanov AV — statistical processing, data analysis, writing the article; Pochernikov DG — patient selection, writing the article; Panacheva EA — literature review, data analysis, patient selection, conducting semen analyses and PCR tests, writing the article.

Compliance with ethical standards: the study was approved by the Ethics Committee of Ural State Medical University, Federal State Budget Educational Institution of Higher Education under the Ministry of Health of the Russian Federation (Protocol № 7 dated September 20, 2019). All patients signed the informed written consent to participation in the study.

Received: 2021-09-16 Accepted: 2021-10-06 Published online: 2021-10-28

The analysis of semen microbiota is difficult due to the lack of established criteria for interpretation of microbiological tests. The aim of the study was to determine the stable clusters of semen microbiota analyzed by real-time PCR in samples with normozoospermia. Semen samples of 227 men with normal spermiograms were included in the study. The quantity of total bacterial DNA and at least one group of microorganisms was more than 103 GE/ml in 107 (41.7%) samples. Four stable microbiota clusters with the prevalence of a specific microorganism group were distinguished in these samples: obligate anaerobes (OA) cluster (proportion in the centroid — 81.1%); Lactobacillus spp. cluster (proportion in the centroid — 64.3%); gram-positive facultative anaerobes (GPFA) cluster (proportion in the centroid — 92.5%); Enterobacteriaceae/Enterococcoccus (EE) cluster (proportion in the centroid — 80.8%). The clusters were ranked by frequency of occurrence: OA cluster was the most prevalent (43 (40.2%) of 107), second-most frequent were GPFA-cluster (27 (25.2%)) and Lactobacillus-cluster (22 (20.6%)). EE-dominated cluster was found in 15 (14.0%) cases.