This study evaluated the effects of inhalation of subanesthetic concentrations of chloroform on rat embryonal and fetal development. Pregnant Sprague-Dawley rats were exposed to 30, 100 or 300 ppm chloroform for 7hr/day on days 6 through 15 of gestation. Exposure to chloroform caused an apparent decrease in the conception rate and a high incidence of fetal resorption (300 ppm), retarded fetal development (30, 100, 300 ppm), decreased fetal body measurements (30, 300 ppm) and a low incidence of acaudate fetuses with imperforate anus (100 ppm). Chloroform was not highly teratogenic but was highly embryotoxic. The results of this study disclosed no relationship between maternal toxicity and embryo or fetotoxicity as the result of exposure to chloroform by inhalation.