The term Neonatal refers to the period immediately succeeding birth and continuing through the first 28 days of extrauterine life. The term also applies to premature infants, postmature infants, and full term infants. Before birth, the term fetus is used.
Neural tube defects (NTDs) are a group of conditions in which an opening in the spinal cord or brain remains from early in human development. In the 3rd week of pregnancy called gastrulation, specialized cells on the dorsal side of the embryo begin to change shape and form the neural tube. When the neural tube does not close completely, an NTD develops.