Endometrial Microbiota Testing
The endometrium
The endometrium is the innermost layer of the uterus. It is a dynamic tissue that undergoes cyclic changes in response to hormonal fluctuations during the menstrual cycle. It is composed of glandular tissue, blood vessels, and a specialised layer of cells called the epithelium. The glandular tissue consists of numerous small glands that secrete mucus and other substances to support embryo implantation and nourishment.
The endometrium is essential for reproductive health and fertility and it plays a crucial role in supporting embryo implantation and pregnancy. Abnormalities or disorders of the endometrium can contribute to infertility, menstrual irregularities, and other reproductive conditions.
Endometrial microbiota
The endometrial microbiota refers to the community of microorganisms that inhabit the endometrium (the lining of the uterus). These microorganisms include bacteria, viruses, fungi, and other microbes that reside within the endometrial tissue.
Disruptions or imbalances in the endometrial microbiota are implicated in infertility and reproductive disorders. The presence of a healthy and diverse endometrial microbiota is thought to play a role in maintaining optimal conditions for successful conception and pregnancy.
Endometrial microbiota testing,
Also known as endometrial microbiome analysis or endometrial microbial profiling, is a diagnostic procedure used to assess the microbial composition and diversity within the endometrium. It involves collecting a sample of endometrial tissue or fluid for analysis to identify and characterize the microorganisms present in the endometrial environment.
This information can help evaluate the health of the endometrial microbiota and its potential impact on fertility, and certain reproductive disorders such as recurrent implantation failure and miscarriage.
How endometrial microbiota can affect fertility
The crucial role of the endometrium in supporting embryo implantation and pregnancy.
Chronic ‘hidden’ infections of the endometrial microbiota
Under normal conditions the endometrium is colonised predominantly by Lactobacilli.
However, under specific conditions such as immunological imbalance (both inherited or acquired) or invasive procedures, the uterine environment can be disturbed and a number of abnormal microbiota populations can develop and colonise the endometrium. In most of these cases, especially acute situations, symptoms are characteristic and become immediately apparent. Following a required course of treatment, a healthy uterine biome is restored.
In some cases, however, the developed abnormal and imbalanced microbiota population falls under a partial control of the immune system. This condition means that smaller populations of invasive bacteria manage to survive within the biota (the immune system preventing an explosion of population but at the same time not removing them completely). These partly controlled populations of microbes are difficult to diagnose as they often cause mild symptoms or asymptomatic conditions. Woman with this chronic condition don’t show obvious or characteristic symptoms of uterine microbiota imbalance but it can have an adverse effect on a future pregnancy.
In cases where immunological imbalance is suspected and the woman suffers from repeated implantation failures, it is useful to the perform endometrial microbiota analysis to detect the present of asymptomatic abnormal bacterial populations in the uterus.
Disrupted endometrial microbiota and impaired embryo implantation
Of the factors that prevent normal implantation and pregnancy, embryo and endometrial quality share responsibility jointly. Here we discuss how an imbalance in the health of the endometrial microenvironment (microbiota) can causes recurrent implantation failure and infertility.
Endometrial / uterine microbiota testing
Uterine microbiota testing typically involves collecting samples from the uterine cavity using minimally invasive techniques such as transcervical swabs or aspirates. These samples are then analyzed using advanced molecular techniques, such as high-throughput DNA sequencing, to identify and characterize the microorganisms present in the sample.
The information obtained from uterine microbiota testing can provide insights into the composition, diversity, and relative abundance of different microbial species within the uterus. Researchers are particularly interested in understanding how alterations in the uterine microbiota may be associated with conditions such as endometritis (inflammation of the uterine lining), infertility, pregnancy complications, and certain gynecological disorders.
Uterine microbiome testing using Next-Generation Sequencing (NGS)
NGS is a powerful technique for studying the microbial composition of the uterus. NGS allows for high-throughput sequencing of DNA samples, providing detailed information about the types and relative abundances of microorganisms present in the uterine microbiota.
It offers several advantages over traditional culture-based methods, as it allows for the identification of a wide range of microorganisms, including bacteria, viruses, fungi, and other microbes. It also provides a more comprehensive view of the microbial community and can detect low-abundance microorganisms that may be missed by culture-based techniques.
