Investigating the vaginal microbiome's impact on IVF pregnancy outcomes

Associations Between the Vaginal Microbiome, Inflammatory Status and Pregnancy Outcome - a Prospective, Observational Study in Women Undergoing Frozen Embryo Transfers.

Observational Freya Biosciences ApS · NCT05150639

This study is trying to see if the balance of bacteria in the vagina affects pregnancy success for women undergoing IVF with frozen embryos.

Quick facts

Study typeObservational
Enrollment300 (estimated)
Ages18 Years to 44 Years
SexFemale
SponsorFreya Biosciences ApS Industry-sponsored
Locations1 site (Waltham, Massachusetts)
Trial IDNCT05150639 on ClinicalTrials.gov

What this trial studies

This observational study aims to explore the prevalence of vaginal dysbiosis in women undergoing IVF procedures in the US. It will compare the vaginal microbiome composition between pregnant and non-pregnant women who have had frozen embryo transfers. Additionally, the study will assess whether menstrual tissue and cervicovaginal secretions provide complementary biomarker information that reflects the immune and inflammatory status of the reproductive tract, potentially influencing pregnancy success after IVF.

Who should consider this trial

Good fit: Ideal candidates are women aged 18-44 who are undergoing a planned frozen embryo transfer and meet specific health criteria.

Not a fit: Patients with uterine pathologies or those currently taking antibiotics may not benefit from this study.

Why it matters

Potential benefit: If successful, this study could enhance understanding of how vaginal microbiome health affects IVF outcomes, potentially leading to improved pregnancy rates.

How similar studies have performed: While the relationship between the vaginal microbiome and reproductive outcomes is being explored, this specific approach is relatively novel and has not been extensively tested in prior studies.

Eligibility criteria

Show full inclusion / exclusion criteria
Inclusion Criteria:

* Age 18-44 years
* Patients whose written informed consent approved by the Institutional Review Board (IRB) has been obtained, after having been duly informed of the nature of the study and voluntarily accepted to participate after being fully aware of the potential risks, benefits and any discomfort involved.
* Women undergoing a planned frozen embryo transfer
* BMI between 18.5-35 kg/m2 (both included)
* Must be able to understand and read the informed consent form in English.

Exclusion Criteria:

* Current diagnosis of pathologies or malformations that affect the uterine cavity such as polyps, intramural myoma, adhesions, fibroids or hydrosalpinx.
* Any illness or medical condition that is unstable or which, according to medical criteria and Investigator's discretion may put at risk the patient's safety and her compliance in the study.
* Participants currently taking antibiotics or with any known condition requiring regular use of antibiotics, that would suggest the participant is likely to need antibiotic treatment during the observational period of this study.
* Systemic and/or vaginally applied antibiotic use within the last month prior to screening (except for prophylactic antibiotics related to egg retrieval).
* Patients utilizing oral contraceptive pills in the past month
* Latex or silicone allergy (Diva Cup and Vaginal Disc)

Where this trial is running

Waltham, Massachusetts

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 Vaginal Flora Imbalance
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.