1.1. Patients with abruptio placentae may be divided into a toxemic, hypertensive, or vascular disease group and a nontoxemic group. In the former the majority of the cases are associated with a persistent hypertension, which may have been initiated or intensified by the pregnancy rather than with a true preeclampsia and eclampsia. The nontoxemic group is associated with local conditions in the uterus. These may be subinvolution due to multiparity or infection, abnormal implantation, faulty contractions of the uterus, etc.2.2. The hemoglobin, hematocrit and serum protein concentrations are lowered proportionately to the hemorrhage. If the loss of these substances is great enough, death may occur as a result of tissue anoxemia and improper interchange of water and electrolysis.3.3. The determination of the hemoglobin and serum protein concentration on admission does not, as a rule, give a true index of the volume of the hemorrhage or of the patient's condition.4.4. The systolic blood pressure on admission may be 100 mm. or more, and yet the patient may be in shock.5.5. The blood fibrin may also be reduced to a concentration which predisposes to bleeding from mucous surfaces, incisions, and the uterus.6.6. The renal function is impaired in many cases but returns to normal after an interval of several months. These tests demonstrate that a chronic nephritis is not present.7.7. The prevention or cure of the associated phenomena is the prompt, adequate, and continued administration of blood and parenteral fluids.