Unlocking uterine biology at home: a validated platform for transforming menstrual effluence into a window on reproductive health

IntroductionAccess to accurate, non-invasive diagnostics remains a critical unmet need in womens health. Menstrual effluence, containing endometrial tissue, immune cells, and microbial communities, represents a clinically relevant specimen for genomic and molecular pathology applications, yet has historically been underutilized due to concerns about sample integrity and variability. MethodsWe developed and validated a standardized, at-home tampon-based collection system designed to preserve nucleic acids at ambient temperature for clinical-grade analyses. 1,067 tampon samples from 328 participants underwent, RNA sequencing and metatranscriptomic profiling to assess specimen transcript integrity, diagnostic fidelity, and microbial composition over time. 12 patients were exome sequenced using matched menstrual effluence and whole blood to assess assay concordance between sample types. ResultsRNA extracted from menstrual effluence maintained stability for up to 14 days without refrigeration, achieving sufficient yield and quality for sequencing in >97% of samples. Variant detection via exome sequencing demonstrated 100% concordance among overlapping single nucleotide variants between menstrual fluid and matched venous blood, confirming clinical equivalency for genetic testing. Transcriptomic analyses revealed cycle-dependent variation in key reproductive and immune markers, while metatranscriptomic profiling identified shifts in microbial communities consistent with known reproductive tract dysbiosis. ConclusionsStandardized at-home collection of menstrual effluence provides a clinically actionable platform that supports remote specimen acquisition without compromising molecular assay fidelity, offering a scalable solution to improve access to carrier screening, reproductive health assessment, and infectious disease monitoring in clinical practice.