Association between small for gestational age and motor coordination difficulties in children aged 5–6 years: Insights from the Hokkaido Study on Environment and Children's Health

Background: Developmental coordination disorder (DCD) presents motor skill delays in early childhood and has been associated with later maladaptation, necessitating early intervention. However, research on the potential risk factors, particularly in preschool-aged children, remains scarce. Aims: We aimed to explore the association between small for gestational age (SGA) and other factors and motor coordination problems in 5–6-year-olds from the Hokkaido Study on Environment and Children's Health Cohort. Study design: Prospective. Subjects: We analyzed data from >3500 participants from the Hokkaido Study, a prospective birth cohort, and assessed children aged 5–6 years. Outcome measures: Participants underwent assessment with the Developmental Coordination Disorder Questionnaire Japanese version (DCDQ-J). We conducted linear regression analyses adjusted for variables such as the child's sex, maternal age, and maternal smoking history during pregnancy, while also examining the independent associations of each risk factor. Results: Among the 3883 children analyzed for SGA, children with SGA exhibited significantly lower DCDQ-J total scores than non-SGA children (mean difference: −2.25, 95 % confidence interval [−4.19, −0.30], p = 0.02). On the subscales, children with SGA demonstrated significantly lower “Control During Movement” scores than non-SGA children (mean difference: −0.96, 95 % confidence interval [−1.78, −0.13], p = 0.02). Furthermore, the child's sex, maternal smoking, maternal age, and preterm birth were independently associated with DCD. Conclusions: SGA was shown to be one of the risk factors for the manifestation of motor coordination difficulties in 5–6-years old children. In combination with other factors, screening for motor coordination difficulties in SGA children will be an important means of initiating appropriate interventions.