What are common clinical features of placental abruption?

Placental abruption is characterized by the premature separation of the placenta from the uterine wall, and its hallmark clinical features include vaginal bleeding and abdominal pain. The bleeding associated with placental abruption may be either visible or concealed, depending on the degree of separation and the location of the bleeding. Abdominal pain typically presents suddenly and can be severe, often described as crampy and persistent. These symptoms arise because the detachment can lead to bleeding and uterine irritability, causing acute discomfort.

In contrast, excessive vomiting is not a typical manifestation of placental abruption; it is more commonly associated with conditions like hyperemesis gravidarum during early pregnancy. Increased fetal movement may be present initially but can be misleading, as fetal movement may decrease if the fetus is in distress due to reduced oxygenation from abruption. Similarly, low fetal heart rate can occur in cases of fetal distress related to abruption, but this is not a primary clinical feature; instead, it is a secondary finding that can occur due to complications arising from the condition. Thus, the combination of vaginal bleeding and abdominal pain is crucial for identifying and diagnosing placental abruption.