Reframing Endometrial Physiology by Advanced Integrated Research (REPAIR)

Heavy menstrual bleeding (HMB) affects 1 in 3 women and can significantly impact quality of life. Despite its prevalence, there is no accessible and accurate diagnostic test. This research will use wearable sensors, magnetic resonance imaging (MRI) scans, and biological sample collection to identify changes in the uterus linked with HMB. The investigators aim to recruit approximately 130 participants across two study sites over three years, including people with and without HMB.

Study Overview

• Status: Recruiting
• Conditions: Menorrhagia Due to Benign Causes

Detailed Description

Heavy menstrual bleeding (HMB) affects up to one-third of women of reproductive age, with a greater prevalence than asthma or diabetes, yet it remains under-recognised and undertreated. HMB is both a symptom and a potential signal of underlying reproductive or systemic dysfunction, including coagulopathies, vascular fragility, inflammation, and abnormal uterine contractility. Its impact is profound, physically, emotionally, and socioeconomically, but current diagnostic practice relies heavily on subjective reporting.

Objective assessment of blood loss is possible with the alkaline haematin test, the gold standard, but it is rarely used in clinical settings due to logistical barriers. This has led to misclassification in research and clinical care, limiting progress in understanding the mechanisms of HMB. Emerging evidence suggests that subtle abnormalities in uterine peristalsis, endometrial repair, and tissue composition may be detectable with advanced imaging and electrophysiology.

The REPAIR study addresses this by integrating anatomical (MRI), functional (wearable electrophysiology), and biological (biosample analysis) measures in women with and without objectively confirmed HMB. This approach aims to establish reproducible physiological signatures that could form the basis of scalable, non-invasive diagnostics.

• Study Type: Observational
• Enrollment (Estimated): 100

Contacts and Locations

• Study Contact: Name: Ying Cheong; Phone Number: +44 7977011443; Email: y.cheong@soton.ac.uk

Study Locations

• United Kingdom
  • Southampton, United Kingdom, so16 6yd
    • Recruiting
    • University Hospital Southampton

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult
• Accepts Healthy Volunteers: Yes

• Sampling Method: Non-Probability Sample

Study Population

Participants will be recruited from in and around Hampshire with the ability to attend Southampton General Hospital for appointments. They will be recruited from both within hospital settings but also the community as many women suffer with HMB without seeking support.

Description

Inclusion Criteria:

• 18-45
• Having Periods

Exclusion Criteria:

• Currently pregnant or breastfeeding.
• Known uterine malignancy, severe anaemia requiring urgent treatment, or other acute gynaecological emergencies.
• Inability to undergo MRI (e.g., pacemaker, severe claustrophobia).
• Inability to provide informed consent.
• Current use of hormonal treatment, or use in the last 2 months

Study Plan

How is the study designed?

Number of groups / cohorts

2

Cohorts and Interventions

Group / Cohort
Menorrhagia; diagnosed heavy periods with haematin test (>/80ml)
Normal periods; not diagnosed as heavy with haematin test (<80ml)

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Frequency of uterine contractions (contractions per minute) measured using cine MRI (HASTE vs TRUFI sequences)	Frequency of uterine contractions quantified from cine MRI sequences and compared between participants with heavy menstrual bleeding and controls.	Cycle 1, Days 18-21 (luteal phase; each cycle is 28 days)

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Dominant frequency of uterine bioelectrical activity measured by wearable pelvic electrodes	Dominant frequency (Hz) of uterine bioelectrical signals recorded using wearable pelvic surface electrodes and analysed using frequency-domain methods.	Cycle 1, Days 18-21 (luteal phase) and Cycle 2 Days 1-5 (menstruation) (each cycle is 28 days)
Acceptability of wearing device (usability score)	Participant-reported usability and acceptability assessed using a structured usability questionnaire developed for this study, comprising 9 items with ordinal response scales. Responses will be assigned numerical values and summed to generate a composite usability score (range 9-36, with higher scores indicating greater acceptability).	Cycle 2, Days 1-5 (menstruation; each cycle is 28 days)
Molecular markers in endometrial biopsy sample	Quantification of molecular biomarkers in endometrial biopsy tissue using histological and molecular analysis techniques (units dependent on biomarker, e.g., pg/mg tissue).	Cycle 1 (each cycle is 28 days), assessed at Days 1-5 (menstruation) and Days 18-21 (luteal phase)
Molecular markers in vaginal swab samples	Measurement of molecular markers from vaginal swabs using laboratory-based assays.	Cycle 1, Days 1-5 (menstruation); Days 6-10 (post-menstruation); and Days 18-21 (luteal phase) (each cycle is 28 days)
Molecular markers in menstrual effluent	Analysis of biomarkers in menstrual effluent collected during menstruation.	Cycle 1 (each cycle is 28 days), assessed at Days 1-3 (menstruation)
Concentration of molecular biomarkers in blood samples	Measurement of circulating biomarkers in peripheral blood samples using laboratory assays (units dependent on biomarker, e.g., pg/mL).	Baseline

Collaborators and Investigators

• Sponsor: University Hospital Southampton NHS Foundation Trust
• Collaborators: University of Auckland, New Zealand
• Investigators: Principal Investigator: Ying Cheong, University Hospital Southampton NHS Foundation Trust

Study record dates

Study Major Dates

• Study Start (Actual): February 6, 2026
• Primary Completion (Estimated): February 1, 2029
• Study Completion (Estimated): February 1, 2030

Study Registration Dates

• First Submitted: March 9, 2026
• First Submitted That Met QC Criteria: April 22, 2026
• First Posted (Actual): April 30, 2026

Study Record Updates

• Last Update Posted (Actual): April 30, 2026
• Last Update Submitted That Met QC Criteria: April 22, 2026
• Last Verified: March 1, 2026

More Information

Terms related to this study

• Keywords: electrophysiology; heavy menstrual bleeding; uterine contractility; menorrrhagia
• Additional Relevant MeSH Terms: Urogenital Diseases; Genital Diseases; Pathologic Processes; Female Urogenital Diseases; Female Urogenital Diseases and Pregnancy Complications; Uterine Diseases; Genital Diseases, Female; Hemorrhage; Uterine Hemorrhage; Menstruation Disturbances; Pathological Conditions, Signs and Symptoms; Menorrhagia
• Other Study ID Numbers: O&G0334; 362221 (Other Identifier: IRAS)

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No