Soft Wearable Aptamer Wristband Enables Real-Time Sweat Dual-Hormone Monitoring for Menstrual Cycle Tracking

Noninvasive and longitudinal monitoring of female reproductive hormones could provide valuable information on individualized endocrine dynamics across the menstrual cycle. Here, we developed an integrated wearable electrochemical platform for simultaneous monitoring of estradiol (E2) and progesterone (P4), together with sweat pH and ionic strength. Competitive-displacement aptamer sensing interfaces were constructed for dual-hormone detection, while a Tesla-valve microfluidic network supported passive sweat transport and sequential sample replacement. A flexible wireless electronic system provided multiplexed signal acquisition and wireless data transmission. To improve quantitative reliability under variable sweat conditions, pH-dependent calibration was incorporated into hormone analysis. The platform was evaluated in two volunteers over approximately one complete menstrual cycle, and the longitudinal E2 and P4 profiles obtained by the wearable sensors showed similar temporal trends to those obtained by paired sweat enzyme-linked immunosorbent assay (ELISA) measurements. pH compensation further improved the correlation between sensor and ELISA measurements of hormone concentrations. These results demonstrate the feasibility of integrating dual-hormone sensing, pH-dependent calibration, microfluidic sweat management, and wireless electronics into a wearable platform for longitudinal monitoring of reproductive hormone dynamics.