Smartphone vs Manual Interpretation of Biomarkers for Ovulation and Luteal Phase Detection (SMOM Study)

Comparing Cervical Mucus, PDG, LH, and Basal Body Temperature Combinations for Ovulation and Luteal Phase Identification Using the Premom Smartphone App Versus User-Read Test Results: A Prospective Observational Study

This study will compare different combinations of fertility signs (cervical mucus (CM), luteinizing hormone [LH], pregnanediol glucuronide [PDG], and basal body temperature [BBT]) to determine which are most reliable for identifying ovulation and luteal phase length. Thirty existing Premom App users will track daily observations for three menstrual cycles. Participants will record mucus, perform urine tests, upload test strip photos to the Premom App, and measure BBT. Both participant readings and AI-assisted app readings will be analyzed. The main goal is to find which marker pairings give the most accurate picture of ovulation timing and luteal phase length. Secondary goals include understanding ease of use, the number of tests required, and whether the app improves accuracy.

This study examines how well different combinations of fertility signs-cervical mucus changes, hormone levels in urine, and body temperature-can help identify ovulation and luteal phase length. The study uses the Premom App, which allows users to record fertility signs and take photos of urine hormone test strips for AI-assisted interpretation. Four marker pairs will be compared: Mucus plus PDG, LH plus PDG, Mucus plus BBT, and LH plus BBT. Each participant will track three cycles, with both app-based and user-based readings analyzed. The study will assess which marker pairings are most accurate and user-friendly. Secondary endpoints include usability, test burden, and app vs. participant agreement. Results may support improvements in fertility awareness and digital health tools. Risks are minimal and involve time commitment for daily tracking. **This is an observational study. Participants are not assigned to any intervention; all fertility signs collected are part of their existing self-tracking using the Premom App. The study analyzes these naturally occurring data to compare marker pairings for identifying ovulation and luteal phase length.**

Inclusion Criteria:

• Female, aged 16 to 45
• Natural menstrual cycles equal or less than 35 days
• Off hormonal contraception for more than 3 months
• Current user of the Premom App
• Willing to track cervical mucus, LH, PDG, and BBT for 3 full cycles
• Lives within 50 km of study site in the Ottawa region
• Able to provide informed consent

Exclusion Criteria:

• Pregnant or breastfeeding
• Current hormonal therapy or contraception
• Known anovulatory disorders, e.g., Polycystic Ovary Syndrome, hypothalamic amenorrhea.
• Very irregular or absent cycles
• Not using the Premom App
• Unable or unwilling to complete tracking or provide consent