Neural Tube Defects

**Definition:** Congenital malformations of the central nervous system and adjacent structures related to defective neural tube closure during the first trimester of pregnancy generally occurring between days 18-29 of gestation. Ectodermal and mesodermal malformations (mainly involving the skull and vertebrae) may occur as a result of defects of neural tube closure. (From Joynt, Clinical Neurology, 1992, Ch55, pp31-41)

**Tree numbers:** - C10.500.680 - C16.131.666.680

**Synonyms:** - Developmental Defects, Neural Tube - Developmental Neural Tube Defects - Neural Tube Developmental Defects