Laboratory and Statistical Methods

Harmonised processing across all three countries is intended to reduce inter-site methodological variability. The primary analysis compares pooled tampon and cup periods with pad periods using a mixed-effects linear regression model. Participants self-collect three vaginal swabs two to three days after each menstruation. Extracted DNA is sent to the Arora Lab for bacterial load quantification, amplification, and 16S rRNA gene amplicon sequencing. Microbial profiling uses 16S rRNA sequencing from SMART-eNAT swabs.