Abstract
Background/Objectives: Follow-up studies in very preterm infants are common, but fewer studies are situated in low- or middle-income countries. In a prospective cohort study, we explored longitudinal motor performance trajectories and influencing factors, including an early motor intervention program. Very preterm infants (gestational age < 32 weeks and/or very-low-birth-weight < 1500 g) in the middle-income country of Suriname were included. Methods: We assessed 149 (49.7% boys) infants (mean gestational age 29(+6), mean birth weight 1271 g) at 3, 12, and 24 months with the Bayley Scales of Infant and Toddler Development for fine motor (FM), gross motor (GM), and composite scores (CSs). Influencing perinatal and environmental factors were explored. Delayed-scoring infants were referred to a motor intervention program. Data were analyzed using mixed-model linear regression. Results: The Bayley mean FM and GM scores decreased between 3 and 12 months and stabilized at 24 months. The mean CS at 3, 12, and 24 months was 102.3, 92.7, and 92.2, respectively. The latter two were significantly below the reference values (100, SD 15, p < 0.01). Birth weight z-scores significantly influenced FM (p = 0.013) and CS (p = 0.009); a lower birth weight was associated with initially lower scores and a smaller decline over time than a higher birth weight. The motor intervention program (n = 54) showed no significant interaction effects at all time points after correction for frequency of interventions (no; 1-5; >5 interventions). Conclusions: Motor performance was normal at 3 months and delayed at 12 and 24 months. Birth weight, but not the early intervention program, influenced longitudinal motor trajectories. We recommend follow-up of motor performance and suggest adding the Prechtl General Movement assessment at 3 months of age. The clinical implementation of the early motor invention program needs additional studies to reach an adequate training level.