Four cases of acute fatty liver of pregnancy occurring over a ten year period are reported. All four patients had a caesarean section and one died postoperatively. The seven children (three twin pregnancies) were all alive. The early clinical signs were unspecific. Jaundice was the only one occurring in all patients. Routine biological tests before the jaundice develops may be of help for a diagnosis early enough to start the treatment in patients with unspecific gastrointestinal or hepatic manifestations, especially the liver function and blood coagulation tests. These latter allow to discord the diagnosis of viral hepatitis and the "Haemolysis-Elevated Liver enzyme concentrations-Low Platelets" (HELLP syndrome) respectively. Indeed, only a liver biopsy can ascertain the diagnosis.