Throughout gestation pregnant Wistar rats consumed a nutritious liquid diet containing 35% ethanol-derived calories. Control mothers were fed lab chow. Subsequently, the offspring of the ethanol-fed mothers were found to be impaired on two-way avoidance conditioning when compared to control offspring, but did not differ from controls in their performance on the Hebb-Williams maze. Fostering and cross-fostering procedures indicated that the effect was due to prenatal influences arising from the drug treatment.