Psychophysiologic reactions in the neonate. 2. Effect of maternal medication on the neonate and his behavior.
Blood levels in the neonate tend to be in direct proportion to those in the mother. Circulating levels of barbiturate-like substances in both mother and infant will depend on the maternal liver's ability to detoxify these durgs. In neonates, there seems to be a lag in the decrease of these drug levels in the brain. Immature livers have only a minimum of the enzymes necessary for drug detoxification. For these reasons, prenatally administered drugs seem to have both an immediate and a more prolonged effect on the immature central nervous systems of infants. Clinical comparison of infants whose mothers had been given effective doses of sedative and analgesic drugs with those whose mothers had received little predelivery medication led to certain conclusions regarding delayed drug effects. All the babies were alert and responsive to sensory stimuli for a few hours postdelivery. This was followed by a period of general disorganization which lasted for 2-4 days in the babies whose mothers received no predelivery drugs. This normal period of disorganization was prolonged 1-2 days in those babies whose mothers received predelivery medication. Inhalant anesthesia given during delivery did not have suppressive effects. Babies of the medicated mothers were not as responsive, did not nurse as successfully, and did not begin to gain weight as early as babies of nonmedicated mothers.