Abstract: A system includes an absorbent article that absorbs and contains bodily exudates and comprises an indication unit that generates an optical signal indicative of presence of the bodily exudates within the absorbent article. The indication unit comprises an optical property changing element that changes from having a first optical property to having a second optical property in response to exposure to the bodily exudates. The indication unit further comprises a visual modifying element proximate that provides a visual modification to the second optical property, resulting in the optical signal comprising a third optical property, wherein a sensor device that attaches to the absorbent article detects the presence of the bodily exudates based on recognition of the optical signal comprising the third optical property.