Gestational caffeine modifies offspring behaviour in mice

Dams from two strains of mice, BALB/c and C57BR were treated during gestation with caffeine, at doses of about 60, 80 and 100 mg/kg/day, in their drinking water. The resulting offspring were behaviourally tested over a 6-month period commencing at age 9 months. When compared with controls, mice from dams that had received caffeine demonstrated longer latencies in a passive avoidance test, and differences were also noted for female C57BR offspring in activity and habituation measures. Having controlled as far as possible for post-natal maternal and environmental effects, the most likely conclusion is that caffeine has a direct pharmacological action on the foetus, and should therefore be classed as a behavioural teratogen in mice.