Prevalence and Temporal Trends of Deformational Plagiocephaly and Brachycephaly in Finland: A Population-Based Register Study

This nationwide population-based study evaluated national trends in the prevalence of deformational plagiocephaly (DP) and deformational brachycephaly (DB) in Finland, using comprehensive registry data. We analyzed 1,453,780 births in Finland between 1987 and 2010. We identified 467 children diagnosed with DP or DB, including one stillbirth. Data were obtained from national health registers and supplemented with individual medical record reviews. Diagnoses were confirmed or corrected, and patients with craniosynostosis were excluded. Although Finland did not launch a formal "Back to Sleep" campaign against sudden infant death syndrome, supine sleep recommendations were gradually adopted and formally revised in 2000. Between 1987 and 2010, DP and DB prevalence rose from 1.7 per 100,000 live births in 1987 to 136 per 100,000 live births in 2010 (P<0.001), with the most pronounced increase occurring after 2000. In the group of children with moderate-to-severe deformities, 62% had no additional anomalies, 29% had 1 to 3 anomalies, and 9% were syndromic. In this group, male predominance (69%) and right-sided occipital flattening (56%) were consistent with findings reported in previous studies. Additionally, the proportion of twins was higher (6.7%) than the national twin birth rate during the same period (2.7%). This study demonstrated a strong temporal correlation between the rising prevalence of DP and DB and evolving supine sleep recommendations in Finland. By the end of the study period, DP and DB prevalence had surpassed that of craniosynostosis, mirroring international trends, although this transition occurred later in Finland than in many other countries.