749 pregnant rats were exposed to a single short wave treatment in the first 16 days of the pregnancy inducing short lasting rectal temperatures of 42°C. Additional investigations were performed at 39 and 41°C and controls were performed at 38°C. On the 20th day of pregnancy 7800 foetuses were delivered by Caesarian section.
No parameters are specified for this exposure.
As a consequence of the hyperthermia treatment numerous malformations arose. The data revealed malformations of the central nervous system, the eys, the tail and extremities as well as cleft palates. The malformation type corresponded to the teratogenic phase at the time of the short wave treatment. Before implantation (i.e. during the first days of pregnancy), the short-wave therapy was lethal for the majority of the embryos.