Not every woman with placenta abruptio has telltale symptoms.

If you have placenta abruptio, you may notice one or more symptoms, including:

• Vaginal bleeding. Depending on the location and amount of separation, vaginal bleeding varies in amount (scant to heavy) and color (bright to dark red). Light vaginal bleeding does not necessarily indicate a minor problem. In some cases, a large amount of blood can be pooled between the placenta and the uterine wall, resulting in little or no vaginal bleeding.
• Uterine tenderness or pain. The uterus may feel hard or rigid.
• Signs of preterm labor. In some women with placenta abruptio, labor symptoms are the first sign of trouble. Labor symptoms can include:
  • Regular contractions.
  • Pain in the abdomen or back. This pain can be sharp or aching.

In rare cases, when heavy blood loss is retained in the uterus behind the placenta, the only signs of placenta abruptio are symptoms of shock. Early signs of shock (most of which are present at the same time) include:

• Lightheadedness or a feeling that you are about to pass out.
• Restlessness, confusion, or feelings of fear or anxiety.
• Shallow, rapid breathing.
• Moist, cool skin or possibly profuse sweating.
• Weakness.
• Thirst, nausea, or vomiting.

High blood pressure (hypertension) is the most common risk factor associated with placenta abruptio. For more information, see the topic Preeclampsia and High Blood Pressure During Pregnancy.