What causes an abdominal hematoma?

September 23, 2025 •

4 min read

An estimated 1.8% of hospitalized patients presenting with abdominal pain are diagnosed with a rectus sheath hematoma, a common type of abdominal hematoma. Understanding what causes an abdominal hematoma is the first step toward effective management and prevention of this condition.

Quick Summary

An abdominal hematoma is typically caused by bleeding into the abdominal wall's muscle layers due to trauma, vigorous exercise, or complications from surgery. A significant risk factor is the use of anticoagulant medications, which can increase the likelihood of spontaneous bleeding.

Key Points

Leading Causes: Abdominal hematomas are frequently caused by trauma (blunt or penetrating), anticoagulant therapy, and activities that increase intra-abdominal pressure like severe coughing or strenuous exercise.
Anticoagulation Risk: Patients on blood-thinning medications have a significantly higher risk of developing a rectus sheath hematoma, which is a common form of abdominal hematoma.
Surgical Complications: Post-surgical hematomas can result from complications during or after abdominal procedures, often due to inadequate control of bleeding vessels or increased patient straining.
Associated Conditions: Certain health issues, such as pregnancy, chronic kidney disease, and blood clotting disorders, increase an individual's susceptibility to developing an abdominal hematoma.
Conservative Treatment: Small, non-expanding hematomas are typically managed conservatively with rest, pain relief, and observation, as the body often reabsorbs the blood over time.
Invasive Intervention: For large or expanding hematomas, especially in hemodynamically unstable patients, procedures like angioembolization or surgery are necessary to stop the bleeding.

What is an Abdominal Hematoma?

An abdominal hematoma is a localized collection of blood in the abdominal area, specifically in an extravascular space. This can occur either within the abdominal wall, known as a rectus sheath hematoma, or deeper within the abdominal cavity (intra-abdominal). The most common type, a rectus sheath hematoma, results from bleeding into the rectus abdominis muscle's protective sheath. These hematomas can range from small, self-resolving bruises to larger, more serious bleeds requiring medical intervention.

Leading Causes and Risk Factors

Several factors can contribute to the development of an abdominal hematoma, ranging from direct physical force to underlying medical conditions.

Trauma

Physical trauma is a primary cause of abdominal hematomas, with both blunt and penetrating injuries capable of damaging blood vessels and causing bleeding.

Blunt force: This includes incidents like motor vehicle accidents, falls, or direct blows to the abdomen during contact sports. The impact can cause vessels to rupture within the muscle tissue.
Penetrating injuries: Stabbings or gunshot wounds can directly sever or puncture blood vessels, leading to hematoma formation.

Anticoagulation Therapy

For many, anticoagulant medication is the most significant risk factor. Studies have shown that a large percentage of patients with abdominal hematomas are on some form of blood-thinning medication, such as warfarin or heparin.

Dosage issues: Incorrect dosage can increase bleeding risk.
Drug interactions: Certain medications and infections can interfere with anticoagulant effectiveness, leading to a higher bleeding risk.
Increased use: The rising use of oral anticoagulants has contributed to an increase in rectus sheath hematoma rates.

Increased Intra-Abdominal Pressure

Excessive force on the abdominal muscles can cause small vessels to rupture, particularly the epigastric arteries.

Strenuous activities: Vigorous exercise, sports like weightlifting or golf, and intense physical strain can all cause muscular tears and vessel damage.
Severe coughing or sneezing: This is a common trigger, especially in patients with respiratory conditions like chronic obstructive pulmonary disease or influenza.
Vomiting or straining: Episodes of severe retching, constipation, or straining during urination can lead to bleeding.

Medical and Surgical Procedures

Sometimes, abdominal hematomas are a complication of medical interventions.

Abdominal surgery: Procedures can cause bleeding due to surgical trauma, inadequate hemostasis, or shearing forces on vessels during muscle retraction.
Percutaneous procedures: Less commonly, procedures like cardiac catheterization or biopsies can lead to hematoma formation if vessels are accidentally punctured.

Other Health Conditions

Certain medical conditions increase a person's susceptibility to bleeding.

Pregnancy: The physical changes of pregnancy, such as hormonal shifts and increased abdominal pressure during labor, can increase the risk of rectus sheath hematomas.
Chronic kidney disease: This condition is linked to an increased risk of abdominal wall hematomas.
Bleeding disorders: Conditions like hemophilia, leukemia, or other coagulopathies disrupt the body's clotting ability.
Vascular diseases: Pre-existing conditions such as atherosclerosis, hypertension, and weakened vessels make them more prone to rupture.

Symptoms and Diagnosis

Recognizing the signs of an abdominal hematoma is crucial for prompt diagnosis. Symptoms often include localized pain, a palpable mass, and in some cases, visible bruising. For deep hematomas, diagnosis typically involves imaging studies like ultrasound or CT scans, which can confirm the presence, size, and location of the blood collection. In severe cases, a significant drop in hemoglobin levels may also be observed.

Treatment Options

Treatment for an abdominal hematoma varies depending on its size and severity.


Treatment Type	When It's Used	Key Actions
Conservative Management	Small, self-limiting hematomas in stable patients.	Rest, pain relievers (non-aspirin), and monitoring. The body naturally reabsorbs the blood over weeks to months.
Coagulation Reversal	For patients on anticoagulants with severe bleeding.	Discontinuing or reversing anticoagulant therapy using agents like Vitamin K or fresh frozen plasma.
Angioembolization	When active arterial bleeding is detected on imaging.	A catheter-based procedure that blocks the bleeding artery, a minimally invasive alternative to surgery.
Surgical Intervention	For large, expanding, or infected hematomas causing hemodynamic instability.	Surgical drainage of the blood clot and ligation of the bleeding vessel.

For most mild cases, conservative treatment is sufficient. However, medical professionals will closely monitor the patient to ensure the hematoma does not worsen or cause complications, such as infection or abscess formation. For hemodynamically unstable patients or those with large, expanding hematomas, invasive intervention is necessary to control the bleeding and prevent life-threatening complications.

Conclusion

An abdominal hematoma can be caused by a variety of factors, from trauma and strenuous exercise to underlying medical conditions and medication use. While many cases are minor and resolve on their own, more severe instances can become life-threatening. Prompt diagnosis, often with the help of imaging, is critical for determining the correct course of action. Whether through conservative treatment or more invasive procedures, effective management of an abdominal hematoma depends on understanding its root cause and addressing the patient's overall health picture. Being aware of the risks, especially for those on anticoagulant therapy, can significantly improve outcomes. For further details on the types and treatment of hematomas, refer to authoritative health resources like the Cleveland Clinic's article on hematomas.

Frequently Asked Questions

The most common cause of an abdominal hematoma is bleeding from the epigastric arteries into the rectus sheath, often triggered by abdominal trauma, vigorous exercise, or severe coughing. Anticoagulation therapy is a significant predisposing factor.

Yes, spontaneous abdominal hematomas can occur, particularly in individuals on anticoagulant therapy, with severe coughing episodes, or those with underlying bleeding disorders. These may happen without any obvious traumatic event.

A rectus sheath hematoma is a specific type of abdominal hematoma, defined as bleeding confined within the rectus abdominis muscle's sheath in the abdominal wall. A general abdominal hematoma can also refer to collections of blood inside the abdominal cavity, known as an intra-abdominal hematoma.

Key risk factors include using anticoagulant medications, older age, being female, having chronic kidney disease, recent abdominal surgery, and conditions that cause severe coughing or straining.

Doctors use physical examination findings, such as the location of pain and presence of a palpable mass, along with imaging tests like ultrasound or CT scans to differentiate. These imaging studies can confirm the presence of blood and rule out conditions like appendicitis or tumors.

No, surgery is not always necessary. Many small, stable hematomas resolve with conservative management, such as rest and pain medication. Surgical intervention is reserved for larger, expanding hematomas, persistent bleeding, or cases where the patient is hemodynamically unstable.

Potential complications include continued severe bleeding leading to hypovolemic shock, infection of the blood collection leading to an abscess, and mass effect causing issues like bladder irritation.