The reproductive Microbiome: a narrative review of the literature

Abstract

Background: Historically, the focus of research around the microbiome has been on pathology, while its physiology has been largely ignored. The importance of this physiological role was demonstrated when the Human Genome Project was published in 2001. Objective: To discuss current research on the female reproductive tract microbiome, in order to provide an expert opinion on how to use this knowledge in the clinical practice in the area of gynecology, obstetrics and infertility. Material and methods: In September ‘20, an electronic search was carried out in PubMed and Google Scholar. The search strategy included keywords related to the scientific literature on the female reproductive tract microbiome, such as (alone or in combination): microflora, microbiota, genital tract, reproduction, semen, vagina, uterus, cervical, placenta, conception, assisted reproduction and the urogenital microbiome. The search was limited to clinical trials, cohort studies (prospective and retrospective) and cross-sectional, systematic reviews, and reviews of the literature published between 2000 and August 2020. Results: A total of 109 articles were identified after the search, of which 73 were eliminated due to duplication, and 4 did not meet the inclusion criteria. In the end, 32 articles were analyzed. After thoroughly reviewing the literature, the most relevant concepts are exposed to understand the impact of the microbiota and its microbiome both in the area of obstetrics, gynecology and reproductive medicine. Conclusions: A comprehensive understanding of the role of the reproductive microbiome guarantees improvements in fertility treatments and of the reproductive health in ge- neral. Although the field is new, there are already ways to use what is known to improve clinical practice and achieve better results in the different facets of a woman's life. Current and future research should discover more ways to regulate the microbiota before conception and during pregnancy to minimize pregnancy loss, preterm labor, and facilitate implan- tation and a full-term delivery, especially of a healthy child.