Chemosensory Development in the Fetus and Newborn

The chemosensory system is one of the earliest emerging systems in fetal development. Smell is detected through the epithelium of the nasopharynx and taste through the tongue. Anatomical structures and innervation are already present in the first and early second trimesters. Early fetal experience with the mother's specific diet through the amniotic fluid provide for a continuous sensory environment from fetal to newborn life. Both term and preterm infants detect and discriminate odor and taste and prefer their own mother's familiar odor and taste. Exposure to the newborn mother's amniotic fluid and breast milk provide physiologic and behavioral changes that influence early attachment relationships and feeding outcomes. Strong, ill-timed, and nonfamiliar odors can interfere with infant physiologic stability and behavioral organization. Hospital chemosensory environments should be adapted to the specific expectations and needs of the infant and mother particularly during delivery and the neonatal intensive care unit experience.