To investigate the scope and impact of multiple malformation/dysmorphology syndromes (Ds) on infant mortality, mental retardation and interactions between perinatology, neonatology, medical genetics, teratology and pediatrics, we analyzed neonatal malformation data and clinical genetic service encounters (GSE) data. Among 4,182 neonates, 153 had significant malformations (3.7%) (“minor” anomalies excluded) and of these, 47 had Ds (31%). Of 12 malformed patients who died during infancy, 6 had Ds. We classified 11,542 GSE accordingly to whether the main concern was clinical(53%), prenatal (43%) or genetic counseling (4%). Of 6,084 clinical-GSE, 2,672(44%) concerned malformations, whereas functional and non-malformative issues represented 30% and 26% of GSE respectively. Most encounters concerning malformations fell in the Ds category (2,026 or 76%), of which 35% could not be fully categorized. Analysis of temporal trends and other variables show that Ds demand a growing share of our efforts.

Formerly, Ds were mostly defined on clinical grounds whereas increasingly molecular/cytogenetic investigations demonstrate new Ds patterns. An investment in Ds data collection calls for novel and Ds specific strategies to capture their complexity. We consider such an effort warranted because of the interdependence and importance of Ds in genetic/teratology research, as well as in academic, clinical and prevention programs.