Immune cells in the uterine lining

Analysis of Immune Cell Populations in the Endometrium and Peripheral Blood in Women With Reduced and Normal Fertility

Observational Jagiellonian University · NCT06826365

This project will test whether the types of immune cells in blood match the immune cells in the uterine lining in women aged 18–45 with unexplained infertility, recurrent miscarriage, or other benign gynecologic reasons who are having an endometrial biopsy.

Quick facts

Study typeObservational
Enrollment50 (estimated)
Ages18 Years to 45 Years
SexFemale
SponsorJagiellonian University Academic / other
Locations1 site (Krakow)
Trial IDNCT06826365 on ClinicalTrials.gov

What this trial studies

This is a cross-sectional analysis of women aged 18–45 undergoing endometrial aspiration for idiopathic infertility, recurrent miscarriage, or other benign gynecologic indications as a control group. On cycle day 20–22, after a negative beta-hCG, a 2 ml endometrial biopsy (NEXODIS suction) and a 10 ml peripheral blood sample will be collected; endometrial tissue will be processed to single cells and 1 ml reserved for flow cytometry. Labeled blood cells and isolated endometrial cells will be stained with a panel of monoclonal antibodies (CD45, CD56, CD16, CD3, CD64, CD206, CD163, CD80, CD86, CD138) and analyzed on a FACSCanto2 flow cytometer to quantify NK cells, T cells, macrophages and other populations. Results will compare immune cell distributions between blood and endometrium and between diagnostic groups, with clinical characterization by age, BMI, gynecologic and obstetric history.

Who should consider this trial

Good fit: Women 18–45 who are not pregnant and who are undergoing endometrial aspiration for unexplained infertility, recurrent miscarriage, or other benign gynecologic indications, and who meet the timing and exclusion criteria, are ideal candidates.

Not a fit: Women with a miscarriage, abdominal/uterine surgery, active infection or antibiotic therapy within the past three months, or those whose fertility problems have a known non-immune cause are unlikely to benefit from findings of this project.

Why it matters

Potential benefit: If clear blood–endometrium correlations are found, this could lead to better diagnostic markers or targeted approaches for women with implantation failure or recurrent pregnancy loss.

How similar studies have performed: Prior observational work has described distinctive CD56bright uterine NK cells and cyclical shifts in endometrial immune populations, but these findings have not yet produced widely accepted clinical tests or treatments.

Eligibility criteria

Show full inclusion / exclusion criteria
Inclusion Criteria:

* age 18-45 years
* idiopathic infertility
* at least 2 miscarriages
* other benign gynecological conditions subjected to endometrial sampling

Exclusion Criteria:

* miscarriage within last 3 months
* abdominal/uterine surgery within last 3 months
* viral/bacterial infection within last 3 months
* antibiotic therapy within last 3 months

Where this trial is running

Krakow

Study contacts

How to participate

  1. Review the eligibility criteria above with your treating physician.
  2. Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
  3. Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.
Conditions Infertility, FemaleRecurrent MiscarriageGynecologic DiseaseIdiopathic infertilityEndometrial immunologyEndometrial aspiration biopsyRecurrent miscarriage
Last reviewed 2026-06-15 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.