Karalexi MA, Dessypris N, Georgakis MK, et al. - Researchers used 16 population-based Southern-Eastern Europe (SEE) registries (1983-2015), to determine the potential link of birth seasonality with childhood (0-14 years) central nervous system (CNS) tumors, in the context of a SEE consortium. They selected overall 6,014 primary CNS tumor cases. In nine countries with accessible live birth data (n = 4,987), Poisson regression and meta-analyses on birth season were conducted. A slightly raised risk of developing a CNS tumor overall, and of embryonal histology particularly, was observed in children born during winter. Boys showed a higher winter peak of embryonal tumors, particularly during the first four years of life. Lower risk of embryonal tumors was suggested in boys < 5 years born during summer. Among girls (0-14 years) born during spring, a clustering of astrocytomas was also identified. Whether there exists a causal association of birth seasonality with CNS tumors could be refined via expansion of registration and linkage with cytogenetic reports. This step could also help to acquire knowledge on the complex pathophysiology of this lethal disease.