ABSTRACT
Bacteria are considered the cornerstone of human microbiome, as the human body houses 10 times more bacterial cells than human cells, each containing thousands of genes independent of human genome. The bacteria colonizing the genital tract represent 9" of the total human microbiome. The higher stability of vaginal microbiome during pregnancy can be attributed to different factors including a high concentration of estrogen and progesterone, increased glycogen levels in the vaginal epithelium. Endometritis is an inflammation of the inner lining of the uterus, typically classified as acute or chronic. Acute endometritis (AE) is acute inflammation of the endometrium that typically occurs postpartum or postabortion. Chronic endometritis (CE) is a persistent inflammation of the endometrial mucosa. The prevalence of CE in infertile patients has been estimated to range from 2.8" to 39". The mechanism through which CE affects embryonic implantation may involve the alteration of the local microbial environment and may be associated with the dysregulation of cytokines in the endometrium.
