Seasonality and risk factors associated with motor development of full-term infants

Introduction: Different factors affect motor development in the first year of life; the interference of seasonal variation lacks further investigation. Objective: To investigate the influence of seasonality and the protective and risk factors on the motor development of full-term infants, at 7 months and 10 months of age. Method: This study included full-term infants (N=174) who experienced developmental milestones to the 2nd and 3td quarters in summer or winter. Medical records, interviews, and the Alberta Infant Motor Scale were used. Results: The acquisition of setting and crawling was later in the post-winter groups (p<0,001). Regarding groups at risk and without risk of motor delays, a low prevalence of pregnancy planning (p=0.015), a short duration of breastfeeding (p=0.004), and breastfeeding time (p=0.012) was found in the risk group at 7 months. At 10 months, children in the risk group had shorter gestational age (p=0.040), were children of older mothers (p=0.020), had more siblings (p=0.002), higher levels of poverty (p=0.002), and more restrictions of movement (p=0.000). Logistic regression showed that, at 7 months of age, breastfeeding was the variable associated with motor development, while at 10 months, the number of children, poverty, and infant movement restriction were significantly explained the variation in motor development. Conclusion: The cold climate was not an isolated determinant for the risk of delayed motor development; environmental variables were more relevant in the model.