From the Guidelines
Placental abruption can occur without pain, and its diagnosis should not be ruled out based solely on the absence of this symptom. When considering the diagnosis of placental abruption, it is crucial to evaluate the full clinical picture, including signs such as vaginal bleeding, uterine tenderness, abnormal fetal heart rate patterns, or maternal hypovolemia signs like tachycardia or hypotension 1. The pathophysiology of placental abruption explains why pain may not always be present; if blood drains through the cervix or the separation occurs gradually, pain may be minimal or absent. Given the potential for serious complications, healthcare providers should maintain vigilance for abruption, especially in patients with risk factors such as hypertension, trauma, substance use, or previous abruption. Key diagnostic steps include:
- Prompt ultrasound evaluation to assess the placenta and uterus
- Continuous fetal monitoring to detect any abnormalities in fetal heart rate patterns
- Laboratory tests, including complete blood count and coagulation studies, to evaluate for signs of maternal hypovolemia or coagulopathy 1. It is also important to note that while pain is a common symptom, its absence does not rule out placental abruption, and a high index of suspicion should be maintained, particularly in high-risk patients. In cases where placental abruption is suspected or confirmed, management should involve a multidisciplinary approach, similar to that recommended for placenta accreta spectrum, with a team of experienced obstetricians, maternal-fetal medicine subspecialists, and other specialists as needed 1. However, the most recent and highest quality study 1 emphasizes the importance of transabdominal US assessment as the preferred initial procedure for evaluating vaginal bleeding in pregnancy, including the assessment of placental abruption. Therefore, ultrasound evaluation should be promptly performed in any patient with suspected placental abruption, regardless of the presence or absence of pain, to guide further management and improve outcomes.
From the Research
Placental Abruption Without Pain
- Placental abruption is a serious pregnancy complication where the placenta separates from the uterus, and it can occur with or without symptoms such as pain and vaginal bleeding 2, 3, 4, 5, 6.
- The diagnosis of placental abruption is clinical, and it can be challenging when the patient does not exhibit typical symptoms like pain 2, 6.
- Studies have shown that placental abruption can occur without pain, and the diagnosis may be made by inspection of the placenta at delivery or by other clinical findings 6.
- The pathophysiology of placental abruption is not fully understood, but it is thought to involve impaired placentation, placental insufficiency, intrauterine hypoxia, and uteroplacental underperfusion 6.
Clinical Manifestations and Diagnosis
- The clinical manifestations of placental abruption can vary from asymptomatic to severe, with symptoms such as vaginal bleeding, abdominal pain, uterine contractions, and abnormalities in the fetal heart rate tracing 3, 5.
- The diagnosis of placental abruption is always clinical, and ultrasonography and other tests may have limited value in diagnosing the condition 2, 6.
- A clinically useful predictive test is needed to detect individuals at risk of placental abruption, but none has been found to be useful so far 6.
Management and Outcomes
- The management of placental abruption should be individualized based on the severity of the abruption, gestational age, and maternal and fetal status 2, 3, 5.
- In cases where fetal demise has occurred, vaginal delivery is preferable, and disseminated intravascular coagulopathy should be managed aggressively 2.
- Placental abruption is a leading cause of maternal morbidity and perinatal mortality, and prompt delivery by cesarean may be indicated in cases of fetal or maternal compromise 2, 4.