Spontaneous movements in the supine position of preterm infants with intellectual disability

Objective: Spontaneous movements at 2 months of corrected age in preterm infants with intellectual disability (ID) were investigated by assessing individual motor elements separated from movements involving the entire body. Methods: Video recordings of 20 preterm infants with ID (16 males, 4 females; median gestational age 26 weeks; median birth weight 810 g) were analyzed and were compared with those of 21 normal preterm infants (8 males, 13 females; median gestational age 30 weeks; median birth weight 1216 g). Results: In the preterm infants with ID at 2 months corrected age, startle response, lateral decumbent position, predominant shoulder rotation, and maintaining hip adduction were more frequently observed and hand sucking, maintaining shoulder abduction, to-and-fro shoulder abduction, to-and-fro elbow flexion, isolated hip adduction, to-and-fro hip abduction, and leg lift were less frequently seen than in the normal preterm infants (Fisher’s exact test, p < 0.05). Conclusion: Abnormal spontaneous movements at 2 months of age in preterm infants with ID result from persistent immature movements and non-emergence of mature movements.