A Skin-Attachable Flexible System Based on Fiber Bragg Gratings With Multisite Sensing Capacities for Mother and Fetus Health Monitoring

This study proposed an innovative approach to investigate the health of pregnant women and fetuses with high metrological properties and unobtrusiveness. Monitoring health throughout pregnancy allows for the management and prevention of abnormalities in physiological parameters. This is crucial in averting severe complications that could result in maternal and fetal mortality if left unnoticed. Our device consists of a multisensor flexible system that is easy to wear on the abdomen to estimate maternal respiratory and heart rates (RRs and HRs), fetal (FHR), and movement fetal movements (FMs). The sensing core of the system consists of an array of 15 fiber Bragg grating (FBG) sensors enclosed within a flexible substrate in a spiral arrangement to investigate multiple measuring sites simultaneously. The description of the design, fabrication, and metrological characterization of the proposed multisensor flexible system is proposed. The feasibility assessment on healthy subjects and the pilot test on a pregnant woman are also described. Results showed promising capabilities of monitoring RR, HR as well as FHR, and FMs by discriminating chest wall deformations with different amplitudes and dynamics induced by the mentioned activities. These findings proved the need to use a multisensor wearable device with skin-like properties and high spatial resolution for pregnant women capable of detecting both maternal and fetal signals over a large abdominal area.