The effect of benzodiazepines on the fetus and the newborn.

The effect of the maternal use of benzodiazepines (BZD) on the fetus and the newborn infant has been studied in a representative series of 17 newborn infants (BZD group). The pregnancy and the perinatal period were characterized by 20 items. On the 2nd day of life, a neurologic investigation was performed and comprised a total of 38 items, subgrouped into items of reflexes/reactions, tonus, and other symptoms and signs. An optimum finding for each item was selected. The results were compared with a group of 21 newborns fetally exposed to psychotropic drugs other than BZD (drug group) and a reference group of 29 newborns with no known fetal exposure to drugs. Infants in the BZD group had a lower birth weight for birth length, as compared to both the drug group and the reference group. Significant differences in frequency of pre- and perinatal complications and in neuro-behavior between the BZD group and the reference group were found in all groups of items. We conclude that the use of BZD during pregnancy is associated with impaired intrauterine growth and an increased frequency of pre- and perinatal events. It affects the newborn infant neurologically mainly in the form of intoxication and withdrawal symptoms.