congenital deviations from the norm of the structure of an organ, system of organs or an organism. Malformations include the congenital absence of any organ (aplasia, agenesis), its decrease (hypoplasia) or enlargement (macrosomia) in various measures, the location of the organ in an unusual place (ectopy, or dystopia), the presence of additional organs (polydactyly), the fusion of organs or parts with each other (syndactyly), the preservation of embryonic gaps (spinal hernia). The most common malformations are of the musculoskeletal system, face, hard palate. Of the pathologies of the development of internal organs, heart defects are the most common.