System including a wearable absorbent hygiene article and a hygiene monitoring device

A system, comprising:

• a wearable absorbent hygiene article defining a front waist region, a back waist region, a crotch region and a longitudinal axis, the wearable absorbent hygiene article comprising:
• a liquid permeable top layer adapted to face a wearer during use;
• a back layer opposite to the top layer;
• and
• an absorbent core in the crotch region and located between the top layer and the back layer, the absorbent core having a core length along the longitudinal axis;
• and
• a hygiene monitoring device comprising a sensing panel,
• wherein the sensing panel comprises:
• an elongate flexible panel defining a longitudinal axis and comprising a flexible substrate, and
• plates comprising a pair of plates spaced apart from each other, the plates being disposed on the flexible substrate,
• wherein each of the plates is elongate along the longitudinal axis of the elongate flexible panel,
• wherein the hygiene monitoring device is configured to measure an impedance between two of the plates,
• wherein an extent of the plates along the longitudinal axis of the elongate flexible panel defines a sensing length,
• wherein the sensing length is 50% to 100% of the core length, and
• wherein the elongate flexible panel comprises an insulating layer which entirely covers the plates to prevent purely resistive coupling between the plates.