Subchorionic Hematoma – Causes, Symptoms, Diagnosis & Treatment

During pregnancy, the accumulation of blood under the chorion membrane is known as a subchorionic hematoma. This membrane links the mother’s uterine wall to the baby’s amniotic sac. The primary indication is vaginal bleeding, which may be asymptomatic in some individuals. In most cases, subchorionic hematomas resolve spontaneously and do not result in any pregnancy-related issues. However, some women experience bleeding during pregnancy. Although it is not uncommon, it is necessary to delve deeper and get it diagnosed to rule out any pregnancy-related complications. In this article, we shall talk about subchorionic hematoma, which leads to bleeding during the first trimester of pregnancy. Read on to know more.

What Is Subchorionic Haemorrhage?

Chorion is the outer fetal membrane. This membrane is placed between the uterus and the placenta. If the placenta gets detached from the site of implantation, the chorionic membranes form a sac between the placenta and the uterus. These movements result in bleeding, and blood gets collected in the chorion, resulting in a subchorionic hematoma, also called subchorionic bleeding (1).

A sub-chorionic haemorrhage can have variable sizes, from small to large clots. The smaller ones are more prevalent and result in spotting, while the larger ones lead to excessive bleeding. Usually, a subchorionic haemorrhage resolves naturally, and you can still have a healthy pregnancy.

How Common Is a Subchorionic Hematoma?

This condition is detected through ultrasound during the first trimester of pregnancy. Around 25 of every 100 women experience vaginal bleeding during the first half of pregnancy. In addition, women who have undergone IVF are more prone to subchorionic hematoma (2).

How Long Do Subchorionic Hematomas Last?

The healing time for a subchorionic hematoma is variable and cannot be predicted with certainty. While some hematomas may shrink and resolve within a few weeks without causing any complications, others may be large and lead to further issues. A healthcare provider may be able to assess and use an ultrasound to determine if a subchorionic hematoma will heal on its own or require additional medical attention.

How Does It Look on Ultrasound?

Subchorionic hematomas or suspected subchorionic clots are observed in around 11% of pregnancies between 10 and 2o weeks (3). Typically, these occur in women who experience vaginal bleeding. Therefore, it is crucial to differentiate them from regions of nonfusion of the membranes to the uterine wall, which are prevalent before 16 weeks of gestation. Irregular texture to the material observed beneath the membranes and a speckled appearance to the amniotic fluid, instead of a uniform one, are findings that suggest a bleed or hematoma rather than membrane separation.

How Is Subchorionic Hematoma Different From Spotting?

Subchorionic haemorrhage shouldn’t be mistaken for spotting. When you notice just a few spots of blood on your undergarment, it’s spotting. However, subchorionic hematoma results in both bleeding and spotting. It may necessitate panty liners. The bleeding may also be accompanied by severe abdominal pain and dizziness.

Causes of Subchorionic Bleed

Why subchorionic haemorrhage happens is still unknown. However, here are the possible causes of subchorionic hemorrhage:

• Implantation of the fertilised egg leads to cramping and pain.
• The expectant mother’s abdomen is being subjected to extreme trauma.
• Blood coagulation disorders.
• Excessive intake of drugs during early pregnancy.
• Scarring from a dilation and curettage (D&C) procedure or miscarriage.
• The expectant mother’s age is above 35 years.

Can a Subchorionic Hematoma Harm the Baby?

In most cases, a subchorionic hematoma resolves on its own. Subchorionic hematoma towards the end of the first or early second trimester can fractionally tear away the developing placenta from its attachment site. Large hematomas can tear away up to 40% of the placenta from the endometrium and can grow larger in size, thereby applying pressure on the gestational area and rupturing the membrane and leading to abortion. Subchorionic hematomas occurring beneath or at the edge of the placenta or behind an isolated area of the foetal membrane can be a cause of concern. Large intrauterine hematomas can restrict the foetus’s growth and hamper the mother’s health.

Is It Considered as a High-Risk Pregnancy?

The severity of the hematoma and any coexisting medical conditions are determining factors. You will probably be categorised as having a high-risk pregnancy if your bleeding is excessive or if the hematoma is huge. However, if your hematoma is small or only causes light spotting, your doctor could advise having a follow-up ultrasound in a few weeks.

It is important to note that if subchorionic hematoma is appearing in the intrauterine pregnancy with possible fetalk heart sounds, the chances of spontaneous abortion is around 9% and could go up if the patient’s age is 35 years and above or if the hemtoma is large (4).

Symptoms of Subchorionic Bleeding in Pregnancy

Small clots usually don’t show symptoms and can be detected only by ultrasound. The most common symptom of a subchorionic hematoma is vaginal bleeding in the early pregnancy (basically the first half).

Noticeable symptoms of a subchorionic hematoma include:

• Spotting or heavy bleeding
• Vaginal bleeding with or without mild cramping
• Bleeding with pelvic cramps

Many people don’t even experience any bleeding; they get to know about it during their routine ultrasounds.

Diagnosis of Subchorionic Haematoma in Pregnancy

A transvaginal or abdominal scan is done to determine the size and position of the clot, the actual amount of bleeding and the site of the blood collection. It also shows the extent of damage to the placenta. From the appearance, it seems as though a second placenta is present. With the help of the images of the bones, regular sonography appears blackish. Post identification of the blood clots, the sub-chorionic haemorrhage can be diagnosed.

Whether the clots are resolving naturally or continue to grow further may be determined with the help of follow-up ultrasounds.

Who Is at Higher Risk for Subchorionic Hematoma?

A subchorionic hematoma has been linked to various factors. Here are certain cases which could suggest high risk for an individual:

• If you have come across any irregularities in the uterus.
• If you have had a history of uterine infections.
• If you have experienced uterine injuries in the past.
• If you have had a history of miscarriages.
• If your pregnancy is resulting from in vitro fertilisation (IVF) (5).
• If you happen to have high blood pressure.

Complications of Subchorionic Hematoma

A vast majority of cases of subchorionic hematomas don’t have a bigger impact and dissolve on their own. However, a certain number of cases may lead to the following complications (6):

• The placenta can get detached from the uterine wall, posing the risk of preterm birth or miscarriage.
• There’s also a risk of miscarriage.
• In addition to other complications during pregnancy, subchorionic haemorrhage can pose a risk to the life of the foetus.

Treatment for Subchorionic Hematoma

Here are some known and recommended subchorionic bleed treatment options:

• Take bed rest.
• Refrain from sexual intercourse.
• Refrain from lifting heavy weights and standing for long hours.
• Opt for progesterone therapy. Some medical practitioners may prescribe progesterone derivatives and advise if it is to be taken orally or vaginally, depending on your health profile, to treat subchorionic haemorrhage.
• Consume adequate water to prevent dehydration.
• Eat small meals at regular intervals to prevent hunger cramps.
• Increase the intake of fibre and water to prevent constipation.
• Go for ultrasound check-ups regularly.

Is There Any Way to Prevent Subchorionic Hematoma in Pregnancy?

While there is no guaranteed way to prevent a subchorionic hematoma, you can take steps to support a healthy pregnancy. This includes maintaining a balanced diet and taking prenatal vitamins to ensure you and your baby receive essential nutrients. Additionally, avoiding smoking, alcohol, and drugs are recommended, as well as seeking prompt medical care if you experience any concerning symptoms, such as vaginal bleeding and sudden cramps.

When Should You Visit a Doctor?

Subchorionic haemorrhage has mild symptoms, which sometimes go unnoticed. Therefore, we suggest visiting a gynaecologist twice weekly during the first trimester. If there is bleeding or spotting, consult your doctor to identify and address the issue immediately.

FAQs

1. What will happen if the baby is born early?

If a woman is diagnosed with a large subchorionic clot or hematoma before 22 weeks of pregnancy, she must carefully consider the potential consequences of continuing the pregnancy. There is a risk of very premature birth, and if the infant survives, there may be neurological or physical abnormalities. Furthermore, fetal growth issues could lead to early delivery, resulting in adverse neurological or physical outcomes.

2. Can a subchorionic hematoma affect my pregnancy or baby?

Most of the time, a subchorionic hematoma is nothing to worry about. However, for some women, a subchorionic hematoma in the first trimester could be accompanied by an increased risk of placental abruption in the later pregnancy. Although it is rare. In cases where there is a low probability, it’s better to consult a doctor and gain more personalised knowledge about it.

3. Can a subchorionic hematoma cause miscarriage?

In a majority of cases, pregnancy subchorionic hemorrhages or subchorionic hematomas don’t impact you or your baby negatively. However, some conflicting research shows the probability of large subchorionic hematomas linked to miscarriage, preterm birth, preeclampsia, infections, and low birth weight, although rare.

4. Is bed rest mandatory when a pregnant woman has a subchorionic haemorrhage?

No. It’s better to avoid bed rest when having a subchorionic hemorrhage bleeding, as it is linked to blood clots and depression.

5. What are the medical recommendations after a subchorionic clot is suspected?

Suppose an early pregnancy subchorionic hematoma discharge is suspected before 20 weeks of gestation. In that case, the recommended course of action is to advise the mother to reduce activity, avoid travel, and seek medical attention immediately in case of vaginal bleeding, cramps, or contractions. As the pregnancy progresses, the following recommendations may be made:

• Administration of RhoGam if the mother is Rh-negative.
• Educating the mother about the signs and symptoms of preterm labour.
• Regular sonograms assess fetal growth, usually once a month or more frequently, depending on the size and appearance of the suspected bleed and other maternal factors.
• Treatment for preterm labour if contractions occur after 20-22 weeks.
• Hospitalisation, especially if bleeding occurs after 24 weeks.

Subchorionic haemorrhage can be fatal to your baby if not diagnosed on time. If you experience bleeding during pregnancy, consult a gynaecologist and take the necessary precautions.

Also Read:

Early Miscarriage
Blood Clots after Birth
Vaginal Bleeding after C-section

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Sources References

1. Cleveland Clinic – Subchorionic Hematoma

2. European Journal of Obstetrics and Gynecology and Reproductive Biology – Subchorionic hematoma occurs more frequently in in vitro fertilization pregnancy

3. National Library of Medicine – Subchorionic Hemorrhage

4. American Family Physician – First Trimester Bleeding

5. National Library of Medicine – Subchorionic hematoma occurs more frequently in in vitro fertilization pregnancy

6. Obstetrics & Gynecology – Perinatal Outcomes in Women With Subchorionic Hematoma A Systematic Review and Meta-Analysis