Head Circumference Growth during Early Childhood in Internationally Adopted Girls: Is there a Relationship to the Adoption Age?

This study aims to provide data on the longitudinal growth of head circumference during early childhood in internationally adopted girls and to determine whether this growth is related to the adoption age. A prospective observational study was conducted on a cohort of 150 internationally adopted girls in Spain between 2001-2017 whose growth was monitored in a specialized reference center. The girls were divided into three groups based on their age at the time of adoption: Up to 12 months (n = 52), between 13-24 months (n = 50), and between 25-48 months (n = 48). The World Health Organization child growth standards were used to compare mean values, using the WHO Anthro v3.2.2 program. Statistical analysis was carried out using One-way ANOVA Tukey's HSD test and Pearson's correlation coefficient, with a significance level of p < 0.05. We found that the head circumference at the time of adoption was significantly delayed. However, the delay degree was not significantly correlated with the adoption age. Furthermore, the growth pattern after adoption showed a slow and incomplete recovery, regardless of the age at which the adoption took place.