An implantable sensor is provided that includes a piezopolymer sensor element including a body having a plurality of layers of a piezopolymer, and an attachment device configured to hold the piezopolymer sensor element in direct contact with at least one of a bodily fluid and bodily tissue such that the piezopolymer sensor element is configured to bend in response to motion of the at least one of bodily fluid and bodily tissue. A pair of electrodes is attached to the piezopolymer sensor element and the electrodes are configured to collect an electrical charge that is generated within the piezopolymer sensor element due to the bending of the piezopolymer sensor element.