Systems and methods for monitoring penile tumescence are provided that overcome the drawbacks of previously known systems by providing a wearable formed of a flexible and elastic tube having a plurality of sensors disposed on or embedded within it, the wearable configured to be applied to a penis of a subject, and a spaced-apart controller operatively coupled to retrieve data regarding circumferential and axial dimensional changes and penile rigidity from the plurality of sensors and transmit that data to an external computer or smartphone for analysis and display. The plurality of sensors may be coupled to the spaced-apart controller via a flexible lead or wirelessly using a passive RFID system.