Is benzodiazepine use during pregnancy really teratogenic?

Abstract

Benzodiazepines (BDs) have a widespread use among people suffering from anxiety. These drugs easily cross the placenta and may affect the developing embryo and fetus. The literature is divided as to whether BD may cause an increase in spontaneous abortions or congenital anomalies. From the years 1988 to 1996, 756 women called the Israeli TIS concerning exposures to BD prior to or during pregnancy. Of 599 women who called us during pregnancy, we have follow-up information on 460 pregnancies (76.6%). The incidence of congenital anomalies (3.1%) was not different from that found in 424 control pregnancies (2.6%). There was a significantly higher incidence of induced abortions (14.1% vs. 4.7%, P = 0.00) and of spontaneous abortions (8.7% vs. 5.2%, P = 0.01). From an examination of our results, it does not appear that BD during pregnancy caused an increase in the incidence of birth defects. There was no specific defect in the offspring. The increase in the rate of induced abortions is probably related to the counseling of the callers, and the increase in spontaneous abortions seems to be a result of the lower gestational age at the time of counseling in the women exposed to BD. It is unknown whether BD could be responsible for developmental or behavioral problems, which are observed only at a later stage.