The embryotoxicity/teratogenicity of α-cyclodextrin (α-CD) was examined in Wistar Crl:(WI)WU BR rats. α-CD was fed at dietary concentrations of 0, 1.5, 5, 10, or 20% to groups of 25 pregnant female rats from day 0 to 21 of gestation. An additional group received a diet with 20% lactose. The additions to the diet of α-CD and lactose were made at the expense of pregelatinized potato starch. Body weight as well as food and water intake were recorded during the treatment period. The rats were killed on day 21 and examined for standard parameters of maternal reproductive performance. The fetuses were examined for external abnormalities, body weight and crown rump length. Fetuses were examined for skeletal and visceral abnormalities. Generally, α-CD was well tolerated and no deaths occurred in any group. Weight gain and food consumption were similar in all groups during gestation, except for a slightly yet significantly increased food intake in the 20% α-CD group from day 6 to 21. Water intake was similar in all α-CD groups; in the lactose group, it was significantly higher than in the controls. Maternal reproductive performance was not affected by the α-CD treatment. Examination of the fetuses for external, visceral and skeletal changes did not reveal any fetotoxic, embryotoxic, or teratogenic effects of α-CD. In conclusion, no adverse effects were observed at α-CD intakes of up to 20% of the diet, the highest dose level tested at which the rats consumed about 13g/kg bw/day. © 2004 Elsevier Inc. All rights reserved.