A system and method for monitoring blood pressure of a wearer has an inflatable arm cuff that is selectably inflatable to differing air pressures that incorporates a fabric having both a light transmission property and a light reflection property when the fabric is illuminated with light having wavelength(s) in the range from about 400 to about 2200 nanometers. A radiation source and a detector are attached to the fabric in relative positions such that the reception of incident radiation by the detector is directly affected by a change in the amount of light transmitted through the fabric relative to the amount of light reflected by the fabric as the fabric stretches in response to motion in the wearer's body due to changes in the flow of blood through an artery disposed beneath the fabric occurring in consonance with variations in the air pressure within the inflatable cuff.