FertilityniMICROBIOMENCT06920797
New Strategies to Evaluate the Reproductive Tract Microbiome
An observational study of Fertility and Infertility, run by Igenomix at 1 site in Spain.
Trial summary
The goal of this observational study is to evaluate alternative less invasive sampling methods for the analysis of the endometrial microbiome. For that, vaginal swab and endometrial fluid samples will be assessed in comparison with the standard sampling method (an endometrial biopsy), in women aged 18-50 years on an… Read more about this study
- Who is it for?
- Ages 18 to 50 years, women onlyHealthy volunteers can take part
- Conditions the study is for
- Fertility, Infertility, Reproductive Health
- What is being tested?
- Reproductive tract microbiome analysis
- How many people
- 57 participants
- Where
- 1 siteSpain
- Study dates
- 9 Jun 2025to 18 Feb 2026
- Phase
- Observational
- Are there results?
- None posted in the registry
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 to 50 years
- Women only
- Healthy volunteers accepted
- Adult
Study population: Women, between 18 and 50 years, coming form the donor program and/or patients from the General Gynaecology Unit who attend to routine gynaecological controls to the clinic, and whose samples will be taken during the secretory phase of the natural menstrual cycle.
Who may be able to join
- Women, between 18 and 50 years, coming form the donor program and/or patients from the General Gynaecology Unit who attend to routine gynaecological controls to the clinic and who voluntarily accept to participate and sign the corresponding informed consent approved by the Ethics Committee, once they have been dully informed of the study's nature and knoe the potential risks, benefits and discomforts.
Who cannot join
- Ongoing pregnancy.
- Samples not obtained during the secretory phase of a natural cycle.
- Intake of any antibiotic, probiotic and/or antifungal in the 7 days prior to the sample collection of the first cycle.
Trial locations and contacts
1 site in 1 country.
About this study
Official title: Evaluation of New Strategies in the Analysis of the Reproductive Tract Microbiome: A Descriptive Pilot Study
The goal of this observational study is to evaluate alternative less invasive sampling methods for the analysis of the endometrial microbiome. For that, vaginal swab and endometrial fluid samples will be assessed in comparison with the standard sampling method (an endometrial biopsy), in women aged 18-50 years on an oocyte donation program and/or who attend the clinic for routine gynecological controls, and whose samples will be collected during the secretory phase of a natural menstrual cycle. The study aims to:
- Evaluate the pontential of the less invasive techniques to assess the endometrial microbiome, compared to the endometrial biopsy, as well as their safety.
- Evaluate the microbiome's stability in a period of 1 to 3 months.
Participants will undergo a sampling round (of the 3 sampling methods), and then a second round 1, 2 or 3 months later, as assigned by the investigator.
Read the detailed description
The endometrium plays a pivotal role in reproductive health, influencing processes such as implantation and pregnancy. Although the endometrium has generally been considered a tissue free of bacteria, numerous studies have documented the presence of an endometrial microbiome mainly composed of different species from the Lactobacillus genus. The presence of pathogenic bacteria has been shown to disrupt the uterine environment, affecting implantation rates and pregnancy success.
Traditional and emerging sampling methods allow for the study of the microbial profile of the endometrium, but the efficiency and representativeness of these techniques vary. Therefore, this study aims to compare the effectiveness, accuracy, and usefulness of three different sampling methods for microbiome analysis: endometrial biopsy, endometrial fluid, and vaginal swab. Additionally, it seeks to compare the endometrial microbial profiles with the vaginal microbiome to assess whether it may provide indirect information about the upper reproductive tract.
Endometrial biopsy is a gynecological procedure routinely performed in the clinical practice to provide the patient with an analysis of their microbiome before embryo transfer, ensuring that it is carried out in a non-pathological endometrium, especially in patients with previous implantation failures. It is considered the standard for uterine lining sampling but is an invasive technique that, due to the discomfort associated with the procedure itself, may not always be feasible. Endometrial fluid is a less invasive method that offers a potential alternative by collecting cells from the endometrial surface. On the other hand, studying the vaginal microbiome, although it may provide insight into reproductive outcomes, may not accurately reflect the microbiome of the uterine cavity, a key location where implantation and pregnancy occur. By using comprehensive microbiome analysis techniques, this study will assess the microbial populations collected by each method and determine the efficiency and usefulness of each sampling technique.
Through direct comparison, this research aims to establish a clearer understanding of how sampling techniques can impact microbiome analysis in the context of reproductive health. The results obtained could have significant implications for clinical practice, potentially offering less invasive and more accurate methods to evaluate the endometrial microbiome. This study aims not only to redirect our approach to sampling the endometrial microbiome but also to improve our understanding of its role in female reproductive health. Furthermore, it would facilitate the assessment of potential correlations between the endometrial and vaginal microbiomes.
- Conditions
- Fertility, Infertility, Reproductive Health, Microbiome Analysis
- Being tested
- Reproductive tract microbiome analysis
- Keywords
- endometrial microbiome, Microbiome, Reproductive tract, Pathogenic bacteria, Dysbiosis
- Medical subject headings
- Infertility, Dysbiosis
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Reproductive tract microbiome analysisDiagnostic test
Assessment of the endometrial and vaginal microbiome in three different samples: endometrial biopsy (EB), endometrial fluid (EF) and vaginal swab (VS).
| Study group | Role | What they receive |
|---|---|---|
| Endometrial and vaginal microbiome description | Participants in this group will undergo two rounds of samples collection, 1, 2 or 3 months apart, as assigned by the investigator. Receives: Diagnostic Test: Reproductive tract microbiome analysis |
What is being measured
The primary outcome is the main question the study is designed to answer.
Evaluation of minimally invasive techniques for the analysis of the endometrial microbiome
Assessment of the viability and technical reliability of the new sampling techniques (endometrial fluid -EF- and vaginal swab -VS-) to evaluate the endometrial microbiome, compared with the standard sampling technique, the endometrial biopsy - EB-. The endometrial microbiome composition will be determined by DNA extraction and bacterial profiling from the three samples (endometrial biopsy -EB-, endometrial fluid -EF- and vaginal swab -VS-). The EB microbiome will serve as reference and it will be compared with the EF's and VS's microbiome to determine whether they are equivalent.
Measured: From enrollment to the second sampling round (1 to 3 months, depending on the study assigned group))
Secondary outcomes (2)
Evaluation of the inter-cycle consistency of the microbial profile in a period of 1 to 3 months
Comparison of the endometrial microbiome from each patient at 2 different time points, 1, 2 or 3 months apart. The endometrial microbiome of each patient, determined by DNA extraction and bacterial profiling of the three samples, will be compared at two different time points (1, 2 or 3 months apart) to determine the microbiome's and technique stability and robustness.
Measured: From enrollment to the second sampling round (1 to 3 months, depending on the study assigned group))
Safety evaluation of the sampling techniques (EB, EF and VS)
Registration of any relevant adverse events related to the techniques reported by participants
Measured: From enrollment to the end of the study (from 1 to 3 months, depending on the assigned group)
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted10 Apr 2025
- Study start9 Jun 2025
- Primary completion18 Feb 2026
- Study completion18 Feb 2026
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for FertilityStudies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Observational
- Observational model
- Cohort
- Time perspective
- Prospective
- Enrolment
- 57 participants (actual)
Sponsor and investigators
- Lead sponsor
- Igenomix
- Sponsor type
- Industry (pharma, biotech, devices)
- Responsible party
- Sponsor
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT06920797
- Sponsor's protocol ID
- IGX1-MIC-DV-24-04
- Acronym
- niMICROBIOME
- Status last verified
- Apr 2026
- First submitted
- 17 Mar 2025
- Last updated
- 21 Apr 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- No
Study at a glance
From the registry record, last updated by the sponsor on 21 Apr 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Evaluation of New Strategies in the Analysis of the Reproductive Tract Microbiome: A Descriptive Pilot Study
- ClinicalTrials.gov ID
- NCT06920797
- Acronym / sponsor ID
- niMICROBIOME / IGX1-MIC-DV-24-04
- Conditions
- Fertility, Infertility, Reproductive Health, Microbiome Analysis
- Keywords
- endometrial microbiome, Microbiome, Reproductive tract, Pathogenic bacteria, Dysbiosis
- Study type
- Observational
- Recruitment status
- Completed
- Enrolment
- 57 participants (actual)
- Lead sponsor
- IgenomixIndustry (pharma, biotech, devices)
- Study start
- 9 Jun 2025 (actual)
- Primary completion
- 18 Feb 2026 (actual)
- Study completion
- 18 Feb 2026 (actual)
- First posted
- 10 Apr 2025 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
The goal of this observational study is to evaluate alternative less invasive sampling methods for the analysis of the endometrial microbiome. For that, vaginal swab and endometrial fluid samples will be assessed in comparison with the standard sampling method (an endometrial biopsy), in women aged 18-50 years on an oocyte donation program and/or who attend the clinic for routine gynecological controls, and whose samples will be collected during the secretory phase of a natural menstrual cycle. The study aims to:
- Evaluate the pontential of the less invasive techniques to assess the endometrial microbiome, compared to the endometrial biopsy, as well as their safety.
- Evaluate the microbiome's stability in a period of 1 to 3 months.
Participants will undergo a sampling round (of the 3 sampling methods), and then a second round 1, 2 or 3 months later, as assigned by the investigator.
Detailed description
The endometrium plays a pivotal role in reproductive health, influencing processes such as implantation and pregnancy. Although the endometrium has generally been considered a tissue free of bacteria, numerous studies have documented the presence of an endometrial microbiome mainly composed of different species from the Lactobacillus genus. The presence of pathogenic bacteria has been shown to disrupt the uterine environment, affecting implantation rates and pregnancy success.
Traditional and emerging sampling methods allow for the study of the microbial profile of the endometrium, but the efficiency and representativeness of these techniques vary. Therefore, this study aims to compare the effectiveness, accuracy, and usefulness of three different sampling methods for microbiome analysis: endometrial biopsy, endometrial fluid, and vaginal swab. Additionally, it seeks to compare the endometrial microbial profiles with the vaginal microbiome to assess whether it may provide indirect information about the upper reproductive tract.
Endometrial biopsy is a gynecological procedure routinely performed in the clinical practice to provide the patient with an analysis of their microbiome before embryo transfer, ensuring that it is carried out in a non-pathological endometrium, especially in patients with previous implantation failures. It is considered the standard for uterine lining sampling but is an invasive technique that, due to the discomfort associated with the procedure itself, may not always be feasible. Endometrial fluid is a less invasive method that offers a potential alternative by collecting cells from the endometrial surface. On the other hand, studying the vaginal microbiome, although it may provide insight into reproductive outcomes, may not accurately reflect the microbiome of the uterine cavity, a key location where implantation and pregnancy occur. By using comprehensive microbiome analysis techniques, this study will assess the microbial populations collected by each method and determine the efficiency and usefulness of each sampling technique.
Through direct comparison, this research aims to establish a clearer understanding of how sampling techniques can impact microbiome analysis in the context of reproductive health. The results obtained could have significant implications for clinical practice, potentially offering less invasive and more accurate methods to evaluate the endometrial microbiome. This study aims not only to redirect our approach to sampling the endometrial microbiome but also to improve our understanding of its role in female reproductive health. Furthermore, it would facilitate the assessment of potential correlations between the endometrial and vaginal microbiomes.
Study design
- Observational model
- Cohort
- Time perspective
- Prospective
- Number of arms
- 1
| Arm | Type | Receives |
|---|---|---|
| Endometrial and vaginal microbiome description | – | Diagnostic Test: Reproductive tract microbiome analysisParticipants in this group will undergo two rounds of samples collection, 1, 2 or 3 months apart, as assigned by the investigator. |
Who may qualify
- Ages
- 18 to 50 years
- Sex
- Female only
- Healthy volunteers
- Accepted
- Age groups
- Adult
- Study population
- Women, between 18 and 50 years, coming form the donor program and/or patients from the General Gynaecology Unit who attend to routine gynaecological controls to the clinic, and whose samples will be taken during the secretory phase of the natural menstrual cycle.
Key inclusion criteria (1 listed)
- Women, between 18 and 50 years, coming form the donor program and/or patients from the General Gynaecology Unit who attend to routine gynaecological controls to the clinic and who voluntarily accept to participate and sign the corresponding informed consent approved by the Ethics Committee, once they have been dully informed of the study's nature and knoe the potential risks, benefits and discomforts.
Key exclusion criteria (3 listed)
- Ongoing pregnancy.
- Samples not obtained during the secretory phase of a natural cycle.
- Intake of any antibiotic, probiotic and/or antifungal in the 7 days prior to the sample collection of the first cycle.
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| Reproductive tract microbiome analysisAssessment of the endometrial and vaginal microbiome in three different samples: endometrial biopsy (EB), endometrial fluid (EF) and vaginal swab (VS). | Diagnostic test | Endometrial and vaginal microbiome description |
Primary outcome
Evaluation of minimally invasive techniques for the analysis of the endometrial microbiome
Time frame: From enrollment to the second sampling round (1 to 3 months, depending on the study assigned group))
Assessment of the viability and technical reliability of the new sampling techniques (endometrial fluid -EF- and vaginal swab -VS-) to evaluate the endometrial microbiome, compared with the standard sampling technique, the endometrial biopsy - EB-. The endometrial microbiome composition will be determined by DNA extraction and bacterial profiling from the three samples (endometrial biopsy -EB-, endometrial fluid -EF- and vaginal swab -VS-). The EB microbiome will serve as reference and it will be compared with the EF's and VS's microbiome to determine whether they are equivalent.
2 secondary outcomes
Evaluation of the inter-cycle consistency of the microbial profile in a period of 1 to 3 months
Time frame: From enrollment to the second sampling round (1 to 3 months, depending on the study assigned group))
Safety evaluation of the sampling techniques (EB, EF and VS)
Time frame: From enrollment to the end of the study (from 1 to 3 months, depending on the assigned group)
Results and safety
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 21 Apr 2026.
- Individual participant dataSharing planned: No
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.
The record lists no contact. Use the official record to reach the sponsor.
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
An observational study of Fertility and Infertility, run by Igenomix at 1 site in Spain.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 1 inclusion and 3 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: finished, as of the sponsor's last update on 21 Apr 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in Spain. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Evaluation of minimally invasive techniques for the analysis of the endometrial microbiome (time frame: From enrollment to the second sampling round (1 to 3 months, depending on the study assigned group))). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 21 Apr 2026.