How menstrual cups, tampons, and pads affect vaginal microbiota and immunity

Impact of the Use of Internal Menstrual Protections on Immunity and Vaginal Microbiota

Observational Centre National de la Recherche Scientifique, France · NCT07199998

This project will see if using menstrual cups, tampons, or pads is linked to changes in vaginal bacteria, local immune responses, or recurrence of common vaginal infections in adult women.

Quick facts

Study typeObservational
Enrollment300 (estimated)
Ages18 Years to 49 Years
SexFemale
SponsorCentre National de la Recherche Scientifique, France Academic / other
Locations1 site (Paris, Île-de-France Region)
Trial IDNCT07199998 on ClinicalTrials.gov

What this trial studies

The project combines a large online survey of 1,500–1,800 participants about menstrual product habits and self-reported urogenital symptoms with a clinical study of about 300 women grouped by primary menstrual protection (menstrual cup, tampon, or external pad). Clinical participants will undergo gynecological exams and provide vaginal, cervical, urine, and blood samples for microbiome sequencing, immune profiling (cytokines and antibodies), and toxicological assays for environmental pollutants. Analyses will compare microbial composition, local immune markers, and exposure levels across product groups and correlate findings with infection history and symptoms. The work is led by the CNRS in collaboration with Institut Alfred Fournier in Paris.

Who should consider this trial

Good fit: Women aged 18–49 who have menstruated, are in generally good health, covered by national health insurance, able to consent and attend study visits, and who refrain from vaginal sex for 72 hours before sampling are ideal candidates.

Not a fit: People who are pregnant or breastfeeding, HIV-positive, recently diagnosed with chlamydia or syphilis, have significant hormonal or menstrual disorders, or are on recent immunomodulatory treatment are excluded and unlikely to benefit.

Why it matters

Potential benefit: If successful, results could help women choose safer menstrual products and inform guidance to reduce recurrent vaginal infections.

How similar studies have performed: Small prior studies have suggested menstrual products can influence vaginal microbiota, but comprehensive clinical and toxicological comparisons across product types remain limited and partly novel.

Eligibility criteria

Show full inclusion / exclusion criteria
Inclusion Criteria:

* Willingness to comply with all study procedures and availability for the duration of the study.
* Female, aged 18 to 49 years.
* In general good health, as determined by medical history.
* Covered by the national health insurance system.
* Willing to sign a written informed consent form.
* Has already experienced menstruation prior to the start of the study.
* No vaginal sexual intercourse within 72 hours before the study visit.
* Has had at least 6 menstrual periods in the past 12 months.

Exclusion Criteria:

* HIV infection.
* Positive diagnosis for chlamydia or syphilis at screening or within 4 weeks prior to screening.
* History of hormonal disorders or menstrual cycle irregularities.
* Metrorrhagia.
* Pregnancy or breastfeeding.
* Family members or close relatives of the clinical or scientific team.
* Treatment with any medication for chronic inflammatory disease or chronic conditions (e.g., cancer, arthritis, transplantation) within the past 12 months.
* Participation in an ongoing clinical trial.
* Receiving or having received antibiotic treatment within the 4 weeks prior to the study.
* Refusal to be informed in case of detected abnormalities.
* Indistinct use of both tampons and menstrual cups.
* Never having had vaginal penetrative intercourse.

Where this trial is running

Paris, Île-de-France Region

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 Sexual Transmitted DiseaseVaginosis, BacterialMycosisUrogenital DiseaseHPVDysbiosisToxic Shock SyndromeMenstrual Cup
Last reviewed 2026-06-13 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.