uterine microbiome uterine microbiome the uterine microbiome is the commensal, nonpathogenic, bacteria, viruses, yeasts/fungi present in a healthy uterus, amniotic fluid and endometrium and the specific environment which they inhabit. it has been only recently confirmed that the uterus and its tissues are not sterile. due to improved 16s rrna gene sequencing techniques, detection of bacteria that are present in low numbers is possible. using this procedure that allows the detection of bacteria that cannot be cultured outside the body, studies of microbiota present in the uterus are expected to increase. microbiome analysis flowchart uterine microbiome and fertility evidence shows that the presence of uterine bacterial 16s rrna gene amplification is not the result of sampling or analysis error and deserves to be acknowledged. concept of the sterile endometrium, and the uterine compartment in general, is outdated; although the true core uterine microbiome still needs to be assessed, and may vary across cultural and regional divides. functional studies are needed to elucidate the physiological importance of the microbiome in fertility. the challenge of studying reproductive immunology and the microbiota involved is that research on all of the different aspects is still in its infancy; the microbiome, immunity, and endocrinology in pregnancy need to be studied both locally and temporally with placental and fetal development to obtain a more comprehensive overview. characteristics bacteria, viruses and one genus of yeasts are a normal part of the uterus before and during pregnancy. the uterus has been found to possess its own characteristic microbiome that differs significantly from the vaginal microbiome, consisting primarily of lactobacillus species, and at far fewer numbers.in addition, the immune system is able to differentiate between those bacteria normally found in the uterus and those that are pathogenic. hormonal changes have an effect on the microbiota of the uterus. taxa epstein-barr virus commensals escherichia coli candida sp. the organisms listed below have been identified as commensals in the healthy uterus. some also have the potential for growing to the point of causing disease: organism commensal transient potentialpathogen