Screening for placental abruption is usually based on the symptoms, as well as the amount of bleeding and level of pain. Placental abruption is grouped into three categories as follows:
- Grade 1: There is a small amount of vaginal bleeding and some uterine contractions, and no signs of fetal distress or maternal low blood pressure.
- Grade 2: There is a mild to moderate level of bleeding, uterine contractions, and the fetal heart rate may indicate fetal distress.
- Grade 3: There is moderate to severe bleeding (or concealed or hidden bleeding), tetany (or uterine contractions that do not relax), abdominal pain, low blood pressure and fetal death.
In some cases, the placental abruption is not diagnosed until a blood clot is found behind the uterus after deliver.