Evidence that the endometrial microbiota has an effect on implantation success or failure

Abstract

Our results demonstrate the existence of an endometrial microbiota that is highly stable during the acquisition of endometrial receptivity. However, pathological modification of its profile is associated with poor reproductive outcomes for in vitro fertilization patients. This finding adds a novel microbiological dimension to the reproductive process.

Reproductive Microbiomes: Using the Microbiome as a Novel Diagnostic Tool for Endometriosis

“…Consistent with other studies characterizing the uterine bacterial community using next generation sequencing, we demonstrated that the uterine bacterial community is comprised mostly of a Bacteroidetes core, with a large percentage of Firmicutes, specifically Lactobacillus sp. that are commonly found in the vagina, although the uterus is not simply a subset of vaginal microbiota [5][6][7]. Across studies, there is significant variability in the rare taxa detected within the uterine cavity.…”

“…This is apparent within the female reproductive tract [4]. The uterus was once believed to be a sterile environment, but it has recently been shown that numerous, phylogentically diverse organisms may inhabit this organ [5][6][7]. Understanding fluctuations in these organisms may be important for a variety of disease states that influence fertility like polycystic ovarian syndrome, endometriosis, and a variety of bacterial infections.…”

A Novel Contributor to Endometrial Receptivity: Endometrial Microbiota

“…2,3 Recent research has also revealed the importance of endometrial microbiota and its possible impact in endometrial receptivity. 13,14 Until recently, endometrium was classically considered a sterile cavity and when the reproductive system microbiota was considered, vaginal microbiota came to mind. 15 However, new techniques and technologies such as microarrays, DNA fingerprinting, and targeted or whole genome sequencing have empowered the field of metagenomics and have begun to change the way we think of reproductive system microbiota.…”

“…and Mycoplasma hominis and is independent from hormonal regulation. 14 In the future, endometrial microbiota transplantation may be used for recurrent implantation failure patients.…”

“…14,17 Because balance in inflammatory factors is important for regulation of the adhesion of the blastocyst to the epithelial endometrial wall, non-lactobacillus dominated microbiota may cause inflammation in the uterine cavity and impair endometrial receptivity. 14 We need new studies focusing on the interaction between endometrial microbiota and receptivity.…”