From the first months to later ages: Early spontaneous movements and developmental outcomes in extremely low birth weight infants

Background: Extremely low birth weight (ELBW; <1000 g) infants are at high-risk for developmental problems; however, no such long-term study has been conducted in this group before in our country. This study aimed to compare the early spontaneous movements and later developmental outcomes of ELBW infants with those of term born normal birth weight (NBW) infants, and to examine the association between the early spontaneous movements and later developmental outcomes at 9-to 12-months of corrected age and at 24-to 42-months in ELBW infants. Methods: Early spontaneous movements of all infants were assessed using the Motor Optimality Score-Revised (MOS-R) at 9-to 20-weeks of corrected age. Developmental outcomes, including cognitive, language and motor domains, were performed using the Bayley Scales of Infant and Toddler Development-Third Edition (Bayley-III) at 9-to 12-months of corrected age in ELBW infants, and at 24-to 42-months of age in both ELBW and term NBW infants. Results: The study included 61 ELBW infants and 50 term NBW infants. ELBW infants had lower MOS-R results (p = 0.017) and lower cognitive (p < 0.001), language (p < 0.001), and motor domains (p < 0.001) outcomes at 24-to 42-months of age compared to term NBW infants. MOS-R and its subcategories were found to be associated with all Bayley-III domains (r = 0.492–0.603, p < 0.05) at both the 9-to 12-months and 24-to 42-months of age. Conclusions: It is highlighted that ELBW infants have lower results than NBW infants, including MOS-R from the early period of life. MOS-R results may serve as a crucial tool to identify ELBW infants who are at higher risk for developmental parameters.