The pernicious or hemolytic anemia of pregnancy is a special form of severe anemia occurring during the latter months of pregnancy and the puerperium. It closely resembles the ordinary form of pernicious anemia in its hematologic and clinical features, but differs radically in its prognosis. Although the mortality is high in the initial attack, if this is survived, the condition does not recur. Osler, in one of his last publications, stated that these anemias of pregnancy have not had the study they deserve. He reported a group of cases, in which one patient remained in good health for thirty years following the attack. Some patients have even gone through subsequent pregnancies without a recurrence of the anemia. The condition is insidious in onset and apparently related to the physiologic anemia in the early months of pregnancy. It progresses during the latter months of pregnancy and may be of quite high