Effect of position on sleep, heart rate variability, and QT interval in preterm infants at 1 and 3 months' corrected age.

Objective: Prone sleeping position has a strong link to sudden infant death syndrome (SIDS), and the "Back to Sleep" campaign has played an important role in reducing SIDS. We tested the hypothesis that the mechanism of the sleep position effect is based on changes in sleep, arousal, heart rate variability (HRV), and the QT interval of the electrocardiogram.

Study Design: We studied 16 premature infants longitudinally, at 1 and 3 months' corrected age.