Automated Movement Detection Reveals Features Of Maturation In Preterm Infants

Nearly 10% of all births in the United States are preterm. Preterm birth is a major risk for developmental neuromotor disorders. Early characterization of a future developmental outcome is necessary to design early interventions. However, such evaluations are currently subjective and typically happen only several months after birth. The aim of this study was to quantify movement bouts after birth and to determine if features of maturation might be characterized. Four preterm infants were continuously monitored for several months, from a few days after birth until discharge, in the Neonatal Intensive Care Unit. Movement was quantified from the photoplethysmogram using a wavelet-based algorithm. In all 4 infants, maturation was associated with a decrease (p < 0.001) in the occurrence of movement bouts <= 30s and an increase (p < 0.001) in longer movement bouts (> 30s). The distribution of movement durations followed a power law function with its exponent defining the characteristic of the distribution. The exponent significantly increased with post-menstrual age. Future research will test whether these maturational changes can predict developmental outcomes.