Tracking ovulation: Self-test microfluidic chip for personal luteinizing hormone level monitoring

Successful pregnancy requires specific timing of conception. Urinary luteinizing hormone (LH) level that peaks immediately before ovulation is useful to predict ovulation and fertility window to enhance pregnancy rate. However, detecting LH commonly relies on yes/no lateral flow strips with varying thresholds for positives. Such non-quantitative tests may lead to false results because the LH varies its level among individuals and fluctuates its peak with different types. To address this issue, we propose a quantitative rapid test that allows self-monitoring of LH levels. The device avoids external analyzer and equipment, and enables an all-in-chip, sample-to-result operation while maintaining analytical precision. We achieve a limit of detection at 3.1 mIU/ml, high selectivity, and tolerance to a wide pH range. Analysis of 112 urine samples demonstrated strong concordance correlation with the reference ELISA method (ρ c = 0.9135). Our self-contained device establishes a quantitative self-test platform for personalized hormone monitoring, bridging point-of-care convenience and privacy with laboratory-grade accuracy. • A quantitative self-test microfluidic chip for luteinizing hormone (LH) detection. • All-in-chip, sample-to-result operation while maintaining analytical precision • The detection limit of 3.1 mIU/ml, high selectivity, and tolerance to wide pH range • Trials on real urine samples showing high accuracy and necessity of monitoring personal hormone levels with individual variations