Bacterial endotoxin and impaired fetal development

Summary Small doses ofE. coli endotoxin given to pregnant mice on the 13th day of pregnancy caused only a mild maternal illness but induced resorption of approximately half the number of fetuses in each mouse. The remaining live fetuses developed normally and showed no evidence of retarded growth or malformations. The weights of their placentas and maternal spleens increased significantly. Endotoxin given on the 6th day of pregnancy caused a small reduction in fetal weights.Acknowledgments. I am indebted to Mrs.Heather Sandison for technical assistance and to Mr.M. J. R. Healy for statistical examination of the results. Dr.A. B. G. Lansdown kindly advized on the interpretation of histological findings.