be ruled out in order to diagnose placental abruption. Of note, use of magnetic resonance imaging has been found to be highly sensitive in depicting placental abruption, and may be considered if no ultrasound evidence of placental abruption is present, especially if the diagnosis of placental abruption would change management. Classification Based on severity: Class 0: Asymptomatic. Diagnosis is made retrospectively by finding an organized blood clot or a depressed area on a delivered placenta. Class 1: Mild and represents approximately 48% of all cases. Characteristics include the following: No vaginal bleeding to mild vaginal bleeding Slightly tender uterus Normal maternal blood pressure and heart rate No coagulopathy No fetal distress Class 2: Moderate and represents approximately 27% of all cases. Characteristics include the following: No vaginal bleeding to moderate vaginal bleeding Moderate-to-severe uterine tenderness with possible tetanic contractions Maternal tachycardia with orthostatic changes in blood pressure and heart rate Fetal distress Hypofibrinogenemia (i.e., 50–250 mg/dL) Class 3: Severe and represents approximately 24% of all cases. Characteristics include the following: No vaginal bleeding to heavy vaginal bleeding Very painful tetanic uterus Maternal shock Hypofibrinogenemia (i.e., <150 mg/dL) Coagulopathy Fetal death Prevention Although the risk of placental abruption cannot be eliminated, it can be reduced. Avoiding tobacco, alcohol and cocaine during pregnancy decreases the risk. Staying away from activities which have a high risk of physical trauma is also important. Women who have high blood pressure or who have had a previous placental abruption and want to conceive must be closely supervised by a doctor. The risk of placental abruption can be reduced by maintaining a good diet including taking folate, regular sleep patterns and correction of pregnancy-induced hypertension. Use of aspirin before 16 weeks of pregnancy to prevent pre-eclampsia also appears effective at preventing placental abruption. Management Treatment depends on the amount of blood loss and the status of the fetus. If the fetus is less than 36 weeks, and neither mother or fetus are in any distress, then they may simply be monitored in hospital until a change in condition or fetal maturity whichever comes first. Immediate delivery of the fetus may be indicated if the fetus is mature or if the fetus or mother is in distress. Blood volume replacement to maintain blood pressure and blood plasma replacement to maintain fibrinogen levels may be needed. Vaginal birth is usually preferred over Caesarean section unless there is fetal distress.