NCT07265505

Study of Endometrial Immune and Microbiological Modifications in Cases of Recurrent Implantation Failure and/or Recurrent Pregnancy Loss

Study of Immune and Microbiological Modifications of the Endometrium in Cases of Recurrent Implantation Failure and/or Recurrent Pregnancy Loss

• Status: Not Yet Recruiting
• Phase: N/A
• Study type: Interventional
• Enrollment: 100 (estimated)
• Sponsor: Assistance Publique - Hôpitaux de Paris · Academic / Other
• Sex: Female
• Age: 18 Years – 35 Years
• Healthy volunteers: Not accepted

Summary

The IMERR study aims to improve understanding of certain causes of infertility related to recurrent implantation failure (RIF) and/or recurrent pregnancy loss (RPL), conditions that affect many women undergoing assisted reproductive technology (ART). Despite medical advances, some patients repeatedly fail to achieve pregnancy, or experience repeated miscarriages. These situations may be linked to subtle immune or microbial disturbances in the uterus. This study seeks to identify immune and microbiological profiles in the endometrium during the implantation window-a crucial period when the embryo attaches to the uterine wall. We will compare women who have experienced RIF and/or RPL with women who have had no such history. Blood and uterine samples will be analyzed to investigate whether certain immune or microbial features are associated with these reproductive failures. The ultimate goal is to uncover predictive factors that may explain why some women experience implantation failure or pregnancy loss, and to lay the foundation for future personalized treatments to improve reproductive outcomes.

Detailed description

The IMERR study is a prospective, monocentric, controlled interventional study aiming to identify immune and microbiological signatures in the eutopic endometrium of women undergoing ART (IVF/ICSI), with and without a history of recurrent implantation failure (RIF) and/or recurrent pregnancy loss (RPL). RIF is defined as the absence of clinical pregnancy after at least three embryo transfers of good-quality blastocysts, and RPL as two or more consecutive pregnancy losses before 24 weeks of gestation. Participants will be divided into two groups: a study group (with RIF and/or RPL) and a control group (without RIF or RPL). Endometrial biopsies will be collected during the implantation window, alongside peripheral blood and vaginal samples. These samples will undergo immunological and microbiological analyses, including histology, immunophenotyping, and microbiota profiling. The study aims to (i) Characterize immune cell populations in the endometrium and blood, (ii) Investigate the endometrial microbiome and its potential dysbiosis, (iii) Explore associations between these biological profiles and clinical features such as endometriosis, adenomyosis, chronic endometritis, or uterine contractility disorders. The study includes 100 participants and spans a total duration of 60 months (36 months for inclusion and 24 months of follow-up). A subgroup analysis will assess the association between immuno-microbiological profiles and clinical outcomes after embryo transfer within the 24-month post-inclusion period. By identifying predictive markers of RIF and RPL, this study may help establish new diagnostic tools and personalized treatment strategies in reproductive medicine.

Conditions

• Recurrent Implantation Failure
• Recurrent Pregnancy Loss
• Infertility, Female
• Endometrial Diseases
• Endometritis
• Endometriosis
• Adenomyosis

Interventions

Type	Name	Description
DIAGNOSTIC_TEST	Endometrial Biopsy	Endometrial biopsy with Cornier Pipelle (part of the treatment in the RIF/RPL group and some patients of the control group / added for the research for the other patients of the control group)
DIAGNOSTIC_TEST	Vaginal Swab	Vaginal sample collection using a cotton swab. Part of the treatment
DIAGNOSTIC_TEST	Blood sample	Peripheral blood draw. Part of the treatment + 10 mL additional for research
DIAGNOSTIC_TEST	Pelvic ultrasound (±pelvic MRI)	Pelvic ultrasound (±pelvic MRI). Part of the treatment

Timeline

• Start date: 2026-04-01
• Primary completion: 2029-04-01
• Completion: 2031-04-01
• First posted: 2025-12-04
• Last updated: 2026-02-05

Locations

1 site across 1 country: France