Learning About Subchorionic Hematoma
What is a subchorionic hematoma?
A subchorionic hematoma or hemorrhage is bleeding between the wall of the uterus and one of the sacs (chorion) that surround the fetus inside the uterus during pregnancy. It can also happen between the uterine lining and the placenta. It’s a common cause of vaginal bleeding in early pregnancy.
Most subchorionic hematomas stop on their own without affecting the pregnancy. In some cases, especially if the hematoma is large or bleeding is ongoing, there may be a higher risk of complications. For example, miscarriage, placental problems, or preterm birth.
What causes it?
The exact cause is often unknown. In some cases, it may be related to a small separation between the pregnancy sac or placenta and the wall of the uterus.
Certain medical conditions, including clotting disorders, may cause some people to be at higher risk.
What are the symptoms?
The main symptom is bleeding from the vagina. Some people may also have pain or cramping in the belly. Sometimes people have no symptoms. The condition might be found during an ultrasound test that was done for other reasons.
How is it diagnosed?
If you are having symptoms, such as vaginal bleeding, your doctor or midwife will ask about your health history, including:
- Your past pregnancies.
- Any problems you've had with your pregnancies.
- Whether you've had any sexually transmitted infections (STIs) or pelvic inflammatory disease.
You will also be asked whether any bleeding from your vagina is:
- Light or heavy.
- Constant or off and on.
Your doctor or midwife will likely ask if you have belly pain or cramping.
Your doctor or midwife will check your belly and do a vaginal examination to see how much bleeding you have. Your cervix may also be examined.
An ultrasound will usually be done. It can show if there is blood trapped between the chorion and the wall of the uterus.
In cases where you don’t have symptoms, a subchorionic hematoma may be diagnosed during a routine pregnancy ultrasound.
How is it treated?
In most cases, no treatment is needed. The bleeding goes away on its own. Your doctor or midwife may do a follow-up ultrasound.
Your healthcare provider may recommend temporarily avoiding very strenuous activity depending on the amount of bleeding and ultrasound findings. Routine bed rest has not been proven to help the pregnancy go better in this situation.
If the bleeding causes other problems, your doctor or midwife can treat or manage them. For example, you may get treatment if the hematoma makes the placenta separate from the wall of the uterus or causes preterm labour.
Many people with a subchorionic hematoma go on to have a healthy pregnancy and delivery. Especially when the bleeding is mild and the pregnancy is otherwise developing normally.
When should you call for help?
Call your healthcare provider or seek urgent medical attention if you have
- Heavy bleeding.
- Severe abdominal pain.
- Dizziness.
- Fever.
- Leaking fluid.
- Contractions.
Adaptation Date: 07/07/2026
Adapted By: Alberta Health Services
Adaptation Reviewed By: Alberta Health Services
