Understanding
Subchorionic Hematoma
A guide for expecting parents
Information to help you understand this common pregnancy finding
What Is a Subchorionic Hematoma?
A subchorionic hematoma is a collection of blood between the wall of your uterus and the pregnancy sac.
Think of it as a pocket of blood in a space where it normally wouldn't be.
It's found on ultrasound and is one of the most common causes of bleeding in early pregnancy.
Where Is It Located?
This diagram shows the normal pregnancy structures:
The hematoma forms between the chorionic membrane and the uterine wall
Types of Hematomas
Hematomas can occur in different locations around the placenta:
Subchorionic hematomas are most common and typically resolve well
How Common Is This?
pregnancies
About 25% of pregnant women develop a subchorionic hematoma.
You are not alone.
Size Matters
We classify hematomas by comparing them to the size of your pregnancy sac.
of sac size
of sac size
of sac size
Your doctor will measure this on ultrasound
What You Might Notice
Some women have symptoms. Others don't notice anything at all.
Light spotting to heavier flow
Mild to moderate discomfort
Found only on ultrasound
When to Call Your Doctor
Contact your care team if you experience:
- Heavy vaginal bleeding (soaking a pad in an hour)
- Severe abdominal pain or cramping
- Dizziness, lightheadedness, or fainting
- Fever or chills (signs of infection)
- Decreased fetal movement (later in pregnancy)
Will This Go Away?
Most subchorionic hematomas resolve on their own without any treatment or complications.
Your body reabsorbs the blood over time, usually within a few weeks to months.
Your doctor will monitor the hematoma with follow-up ultrasounds
to track changes in size.
What Does Research Show?
A large study of 2,446 women found important reassuring news:
Subchorionic hematoma in the first trimester is NOT independently associated with pregnancy loss before 20 weeks.
This remained true even when researchers accounted for:
- Size of the hematoma
- Presence of vaginal bleeding
- Gestational age at diagnosis
What Are the Risks?
While most hematomas cause no problems, larger ones may be associated with:
- Vaginal bleeding (may be heavy at times)
- Small increased risk of preterm birth
- Rarely, placental abruption in later pregnancy
What Happens Next?
Your monitoring plan:
- Follow-up ultrasounds to track the hematoma
- Regular prenatal visits to monitor your pregnancy
- Watching for symptoms like bleeding or cramping
- Additional ultrasounds if symptoms develop
Each monitoring plan is tailored to your situation
What You Can Do
There's no proven treatment, but these steps may help:
- Rest when you can, especially if you have bleeding
- Avoid heavy lifting and strenuous activity
- Stay hydrated and maintain healthy habits
- Take your prenatal vitamins
- Ask questions at your appointments
- Track any bleeding or symptoms
Note: Some providers recommend pelvic rest (avoiding intercourse and tampons),
though evidence for this is limited
Key Takeaways
- Subchorionic hematomas are common (1 in 4 pregnancies)
- Most resolve on their own without complications
- Research shows they do not independently increase miscarriage risk
- Monitoring with ultrasound helps track changes
- Stay in close communication with your healthcare team
We're Here With You
Your healthcare team is monitoring your pregnancy carefully.
We're partners in this journey together.
Never hesitate to call with questions or concerns.
Stay informed. Stay hopeful.