Endometrial biopsy

Endometrial biopsy or sampling of the endometrial lining is a simple procedure performed in the consultation room following a simple hormonal preparation or in a natural menstrual cycle. It allows the precise testing of the endometrial tissue investigating the window of embryo implantation (WOI), the correct balance of endometrial microbiome or to exclude chronic inflammation of the lining.

Window of implantation (WOI) testing

Endometrial histology to “date” the endometrial lining and determine whether it is suitable for an implanting embryo was used for decades but was found to be not reliable. More recently, more sophisticated testing using a gene expression profile allowed the precise determination of the window of implantation (WOI) to determine whether a lining is normally receptive or whether the WOI is shifted (in up to 30% of tested patients). This would allow personalizing the hormone regimen for embryo transfer and potentially increased success rates.  

Endometrial microbiome testing

With the same endometrial biopsy, the presence and composition of uterine microbes could be also investigated. Lactobacilli are essential for maintaining a healthy vaginal environment. The imbalance of the vaginal and endometrial microbiome could lead to inflammation even infertility. Highly sophisticated DNA-based testing allows the detection of even a tiny number of pathogenic bacteria and targeted treatment.   

Chronic endometritis testing

Chronic endometritis or the chronic inflammation of the uterine lining could be a significant cause of infertility, recurrent implantation failure or pregnancy loss. This could be diagnosed by analyzing the sampled lining with a classical histological examination or by detecting CD-138 markers or studying the composition of the endometrial microbiome.   

Endometrial immune cell testing

The impact of reproductive immunology on pathologies such as recurrent implantation failure or recurrent pregnancy loss is a controversial topic with reproductive medicine. The correct balance of immune cells (such as uterine natural killer, T cell population) in the endometrial lining could be studied by analyzing a biopsy which is taken in a mock cycle. If an immune dysregulation is found this could be treated by different immune modulatory treatments around the time of embryo implantation and early pregnancy.