Abruptio Placentae

A premature separation of a normally implanted placenta from the uterine wall, usually occurring in the third trimester of pregnancy.

Causes and Incidence The etiology is unknown but is believed to be related to hypertensive and cardiovascular disease processes or use of cocaine. Abruptio placentae occurs in 0.5% to 3.5% of all deliveries.

Disease Process The placenta releases from the wall of the uterus, and retroplacental bleeding occurs. The degree of release may vary from a few millimeters to complete detachment. Blood can accumulate under the placenta (concealed hemorrhage) or can be passed behind the membranes and out the cervix (external hemorrhage).

Symptoms The signs and symptoms vary with the degree of separation and the resultant amount of hemorrhage. Severe cases involve slight to profuse vaginal bleeding; maternal shock (hypotension, dizziness, rapid pulse, dyspnea, pallor); sudden, severe pain; tender, tightly contracted uterus; and fetal distress or fetal death.

Potential Complications Hypofibrinogenemia with disseminated intravascular coagulation (DIC), uteroplacental apoplexy (Couvelaire uterus), and renal failure are possible, particularly if the woman has preexisting toxemia.
 

Diagnostic Tests 

Abdominal ultrasound
To rule out placenta previa
 

Treatments 
 
Surgery 
Cesarean section (unless vaginal delivery is imminent) when bleeding cannot be controlled
 
Drugs
None
 
General      
Bed rest until bleeding stops; fluid and volume replacement by intravenous administration; blood replacement if necessary to prevent shock; rupture of membranes if delivery is imminent to reduce the possibility of DIC