Congenital malformations in the rat following induced hyperthermia during gestation

Hyperthermia induced in pregnant rats by exposures for 40 to 60 minutes in an incubator that raised deep body temperatures from 38.1 ± 0.51 to 42.7 ± 0.62°C produced increased fetal resorptions, retardation of growth, and a number of development defects. Grossly apparent fetal malformations included microphthalmia following hyperthermia on day 9 of pregnancy, anencephaly on day 10, and defects of tails, limbs, toes, palate, and body on days 12 to 14.