This work reviews the literature on the development of the tongue and its function during fetal life. Research on fetal behavior in general and functioning of structures of the skull, face and neck during fetal life in particular was very difficult, not to say impossible, until the present era of ultrasonography with flow (color Doppler and power Doppler), as well as 3D and 4D imaging. The results of measurements of the tongue, its perimeter, length, and area in normal fetuses and in fetuses with chromosomal aberrations are discussed. Abnormalities of the tongue appear as isolated defects or in association with other genetic abnormalities. Initial ultrasonographic detection of abnormalities of the fetal tongue demands further examination with more sophisticated sonographic methods. Some researchers also advocate karyotyping. Reports are discussed on the function of the tongue, such as protrusion, licking, grooving, sucking, yawning, and swallowing, and the time during pregnancy when these functions appear concurrently with growing complexity of movements of the fetus. These functions of the tongue have been studied in normal fetuses and in those with abnormalities during fetal life, such as Rh immunization and intrauterine growth retardation. Attention should focus on the presence of fetal tumors of the tongue or floor of the oral cavity. Prenatal diagnosis of tumors of the oral cavity and throat enables treatment to be undertaken immediately after birth and during the neonatal period.