ABSTRACT
The detection of fetal neural tube defects (NTDs) in the second trimester has become a mainstay of noninvasive and invasive prenatal diagnosis for the past 30 years. NTDs are among the most common serious congenital malformations and are the result of the failure of the fetal NTD to close completely; the degree and location of the opening of the neural tube are key determinants of the severity of the defect. This chapter will review the current status of prenatal screening and detection of fetal NTDs.
