Sex-linked differences in avoidance learning in the offspring of rats treated with nicotine during pregnancy.

The offspring of rats treated with nicotine (0.5 mg/kg/day SC) on days 1-20 of gestation, were trained for active avoidance conditioning when 60 days old. Although learning was similar in both control groups of males and females, nicotine exposure during fetal life improved learning in females but reduced it in males, the difference between these two groups being statistically significant from day 17 until the end of the training period (day 25).