title: Fetal and placental responses to artificially induced hyperthermia in rats.
abstract: Pregnant rats were utilized to study the effect of maternal hyperthermia on fetal development. Eight groups of six to eight rats were exposed to ambient temperatures of 43-44 degrees C at various stages of pregnancy. All rats were killed on day 20 of gestation. Edema, microencephaly and microphthalmia followed heat treatment on day 4, 6, or 8 and skeletal defects occurred on day 10 of gestation. Apparently heat stress of dams after day 14 of gestation had little or no effect on embryos. Most placentas from day 6-10 treatment groups were significantly heavier than control and exhibited extensive thickening and necrosis of decidua basalis. Our results suggest that the rat is a useful model for investigating maternal hyperthermia as a possible cause of human placentophathies and fetal retardation.
mesh_terms: D000818:Animals; D001831:Body Temperature; D001842:Bone and Bones / Q000002:abnormalities; D000013:Congenital Abnormalities / Q000209:etiology*; D005260:Female; D005327:Fetal Resorption / Q000209:etiology; D006358:Hot Temperature / Q000009:adverse effects*; D008098:Litter Size; D008297:Male; D009929:Organ Size; D010920:Placenta / Q000473:pathology; D010922:Placenta Diseases / Q000209:etiology*; D011247:Pregnancy; D051381:Rats