Water around the fetal heart causes types symptoms and the latest methods of treatment and prevention

Fluid around a baby's heart during pregnancy is a medical concern that can worry any expectant mother, as it may significantly affect the baby's health if not treated promptly. In this Daily Medical guide, we’ll explore the causes of fluid accumulation around the fetal heart, the different types of this condition, the key symptoms that require immediate medical attention, and the available treatment and prevention methods. Our goal is to help you fully understand the issue so you can take early steps to protect your baby's health. Stay with us for all the details!

Q1: What is fluid around a baby’s heart (pericardial effusion)?

Fluid around a baby’s heart means there is an excess amount of fluid accumulating in the space surrounding the heart inside the pericardial sac. This fluid can put pressure on the heart and affect how it functions.

Q2: What causes fluid to accumulate around the fetal heart?

There are several possible causes for fluid buildup around the baby’s heart, including:

Congenital heart defects
Infections passed to the fetus during pregnancy
Blood-related problems like severe anemia
Lymphatic system disorders
Sometimes, the cause remains unknown.

Q3: What are the symptoms of fluid around the fetal heart?

Most of the time, the mother doesn’t experience any symptoms. However, doctors may detect the fluid during an ultrasound. In some cases, signs like an enlarged abdomen or slow fetal growth might appear.

Q4: How is fluid around the fetal heart diagnosed?

Diagnosis is mainly done using ultrasound imaging, which clearly shows fluid around the heart. A Doppler scan may also be used to assess blood flow, and in complex cases, a fetal MRI might be recommended.

Q5: What are the risks of fluid around a baby’s heart?

If the fluid builds up too much and puts pressure on the heart, it can interfere with its normal function. This might lead to complications such as premature birth, and in severe cases, it may threaten the baby’s life.

Q6: Can fluid around the baby’s heart be prevented?

Prevention is possible to a large extent by:

Regular prenatal checkups
Controlling chronic maternal conditions like diabetes or high blood pressure
Avoiding infections through good hygiene
Eating a healthy, balanced diet
Avoiding smoking and alcohol

Q7: How is fluid around the fetal heart treated?

Treatment depends on the cause and severity. In some cases, doctors may prescribe medication to the mother to reduce the issue while closely monitoring the baby. In rare and serious cases, fetal surgery or specialized care after birth might be necessary.

Q8: Can fluid around the baby’s heart cause problems after birth?

Yes, it may lead to health issues in the baby after birth, such as heart problems or delayed development. That’s why close medical monitoring from day one is essential to ensure the baby’s safety and healthy growth.

Q9: What tests are needed to monitor fluid around the baby’s heart?

Monitoring usually involves regular ultrasounds to track the fluid levels and heart condition. Doppler scans may be used to check blood flow, and blood tests from the mother may be done to identify infections or other health issues.

Q10: Does fluid around the baby’s heart affect the mother’s health?

Usually, this condition does not directly affect the mother’s health. However, it does require ongoing medical follow-up, which may cause stress and anxiety during pregnancy.

Causes of Fluid Around a Baby’s Heart

Fluid around the fetal heart can result from various causes, both natural and medical. Here’s a simple breakdown of the most common ones:

1. Normal Development Stage

In early pregnancy, a small amount of fluid may be seen around the baby’s heart as a part of its normal development. It often disappears on its own without intervention.

2. Ultrasound Error or Imaging Illusion

Sometimes, what appears to be fluid is just a visual artifact caused by the angle of the scan or light reflection, and it’s not an actual problem.

3. Viral Infections During Pregnancy

Certain viruses can pass from the mother to the fetus and cause fluid buildup, such as:

Cytomegalovirus (CMV)
Parvovirus B19
Rubella (German measles)

4. Severe Anemia

If the baby suffers from serious anemia due to infection or immune issues, the body may retain fluid around the heart.

5. Congenital Heart Defects

Some structural heart problems can disrupt normal blood flow, leading to fluid accumulation.

6. Chromosomal Abnormalities

Conditions like Down syndrome, Turner syndrome, or Edwards syndrome can interfere with fetal development and lead to fluid buildup.

7. Hydrops Fetalis

A serious condition where fluid collects in multiple areas of the baby’s body, including around the heart. It can be caused by heart disease, infections, or immune system problems.

8. Lymphatic System Disorders

If the lymphatic system isn’t draining fluids properly, fluid can build up around the heart.

9. Autoimmune Disorders in the Mother

Diseases like lupus or antiphospholipid syndrome can affect the fetus and result in fluid accumulation.

10. Liver or Kidney Dysfunction in the Fetus

If the baby’s liver or kidneys aren’t functioning well, fluid may not be processed properly and can build up.

11. Low Protein Levels in the Fetus

A lack of proteins like albumin in the blood can cause fluid to leak and accumulate.

12. Blocked Major Veins

If major veins leading back to the heart are blocked or malformed, pressure may cause fluid to collect around the heart.

13. Harmful Medications During Pregnancy

Some medications taken during pregnancy can affect heart development and lead to fluid buildup.

14. Tumors in the Heart or Chest

Rarely, a small tumor can press on the heart and cause fluid accumulation.

15. Severe Fetal Anemia (like Thalassemia)

Certain types of anemia, such as thalassemia, can lead to heart failure and fluid buildup.

16. Preeclampsia or Placental Issues

If the placenta isn’t delivering enough oxygen, the fetus may be affected and start to retain fluid.

17. Weakness in the Heart Membrane

If the membrane around the heart is weak, it may allow fluid to collect more easily.

18. Problems Absorbing Amniotic Fluid

Digestive or urinary tract issues can affect the baby’s fluid balance and lead to accumulation around the heart.

19. Inherited Metabolic Disorders

Some rare genetic conditions affect how the body processes nutrients, which can lead to fluid retention.

20. Mechanical Pressure in the Uterus

Multiple fetuses or uterine tumors may press on the baby and interfere with blood flow, causing fluid buildup.

Types of Fluid Around the Fetal Heart (Pericardial Effusion)

The presence of fluid around the fetal heart can vary in amount and cause, which affects how the condition is managed. Here’s a simplified breakdown of the types:

1. Mild Pericardial Effusion

This is when there's a very small amount of fluid around the heart. It's usually temporary and doesn’t affect the baby. In most cases, it resolves on its own without treatment.

2. Moderate Pericardial Effusion

The fluid is moderate in amount and may slightly compress the heart’s movement. Careful monitoring is required to see if the condition improves or worsens.

3. Severe Pericardial Effusion

A large amount of fluid accumulates and puts significant pressure on the heart, affecting its function. This is a serious condition and requires urgent medical attention and special care.

4. Primary Pericardial Effusion

This happens due to issues within the heart itself, such as congenital heart defects or problems with the pericardial sac (the membrane that surrounds the heart).

5. Secondary Pericardial Effusion

This type results from other conditions affecting the baby or the mother, like infections, anemia, or lymphatic system disorders.

6. Pericardial Effusion with Cardiomegaly

In some cases, fluid is present around the heart along with an enlarged heart, indicating chronic or serious heart conditions.

7. Chronic Pericardial Effusion

This is when fluid persists for a long time and gradually increases, potentially affecting the heart’s growth and long-term function.

⚠️ Symptoms of Fluid Around the Fetal Heart (Pericardial Effusion)

Since the fetus cannot express discomfort, doctors usually detect pericardial effusion through ultrasound or advanced pregnancy scans. Here are the main signs and symptoms:

1. Fluid Around the Heart on Ultrasound

This is the first and clearest sign—appearing as a layer of fluid around the heart, which may be thin or thick depending on the case.

2. Enlarged Heart

If the fluid compresses the heart, it may appear larger than normal, and sometimes there is reduced heart motion.

3. Signs of Hydrops Fetalis

In severe cases, fluid may collect in other parts of the baby’s body, such as:

Fluid in the abdomen
Swelling under the skin
Fluid around the lungs
Enlarged placenta

4. Abnormal Fetal Movement

You might notice that your baby’s movements have slowed down or weakened, due to the fluid affecting the heart or other organs.

5. Irregular Fetal Heartbeat

The doctor may notice:

Unusual fast or slow heart rates
Or irregular heartbeat patterns

6. Poor Blood Flow in the Umbilical Cord

Through a Doppler scan, reduced blood flow may appear due to the pressure from the fluid.

7. Symptoms in the Mother

In severe cases:

A sudden increase in abdominal size
Or an increase in amniotic fluid volume

8. Delayed or Poor Fetal Growth

Excess fluid may affect the baby’s nutrition, leading to poor growth.

9. Increased Amniotic Fluid (Polyhydramnios)

Some cases involve too much amniotic fluid, due to swallowing issues or heart problems.

10. Swelling in the Baby’s Body

You may see facial or limb swelling on ultrasound—often due to fetal hydrops.

11. Breathing Problems After Birth

If the case is severe, the baby may be born with difficulty breathing, caused by fluid pressure on the lungs before birth.

12. Sudden Drop in Fetal Heart Rate During Labor

The fluid may affect heart efficiency, which shows as abnormal fetal heart rate during delivery monitoring.

13. Poor Placental Function

Pressure on the heart may reduce blood pumping, making the placenta less effective.

14. Jerky or Unusual Movements in the Fetus

Sometimes, the ultrasound shows unusual or shaky movements, possibly due to fluid affecting the nervous system.

15. Poor Fetal Circulation

Fluid around the heart may limit the heart’s ability to circulate blood well, and this shows up in Doppler tests.

16. Low Blood Pressure in the Fetus

If blood isn’t pumped effectively, it may lead to reduced pressure in fetal vessels.

17. Abnormal CTG Results

This includes continuous acceleration or deceleration in fetal heart rate patterns.

18. Abnormal Amniotic Fluid Color

If the amniotic fluid appears green or dark, it may indicate fetal distress or lack of oxygen.

19. Signs of Genetic Syndromes

Pericardial effusion can sometimes be linked to congenital syndromes like Down or Turner syndrome, often accompanied by other signs.

20. Malformations in Other Organs

Such as the lungs, kidneys, or nervous system—especially if the underlying cause is a congenital defect.

21. Poor Response to Stimulation

If the doctor tries to stimulate the baby via ultrasound and there’s no reaction, it may indicate poor circulation.

22. Abnormal Heart Shape

Too much fluid can cause temporary deformation or swelling of the heart.

23. Diaphragmatic Flutter

Ultrasound may show rapid or irregular movements in the baby’s chest, possibly due to internal pressure on the heart or lungs.

How to Detect Fluid Around a Fetal Heart (Diagnosis Methods)

Regular Ultrasound
This is usually the first step. The doctor can see if there’s any fluid around the baby’s heart.
The fluid appears as a “halo” around the heart muscle. The doctor will assess if it’s a small or large amount.
Fetal Echocardiography
A more detailed ultrasound done by a specialist. It shows the structure, movement, and function of the fetal heart, helping to detect any weakness or abnormalities.
Amniocentesis
A sample of amniotic fluid is taken and tested to check for viral infections or genetic issues that may be causing the fluid buildup around the heart.
Maternal Blood Tests
These help detect infections or immune-related diseases that could affect the fetus. Blood tests may also screen for certain viruses or antibodies.
Chromosome Testing (NIPT)
A modern non-invasive test done using the mother's blood. It can detect chromosomal disorders like Down syndrome.
Fetal Heart Monitoring (CTG or NST)
A simple device placed on the mother's belly records the baby’s heartbeat, helping detect any stress or irregularities.
Fetal MRI
Used in special cases when more detailed imaging is needed around the heart or other organs. It’s not commonly used but provides highly accurate information.

Other Helpful Diagnostic Tools:

Doppler Ultrasound: Measures blood flow in the heart and vessels.
3D/4D Ultrasound: Offers a clearer view of the heart and surrounding fluid.
Additional Maternal Blood Tests: To check hormone levels or proteins that may affect pregnancy.
Serial Ultrasounds: Regular scans to monitor whether the fluid is increasing or decreasing.

What Are the Risks of Fluid Around the Fetal Heart?

Cardiac Tamponade
The fluid may put pressure on the heart, reducing its ability to pump blood efficiently, which affects circulation.
Weak Heart Muscle
If the heart isn’t functioning well, it may slow down fetal growth.
Hydrops Fetalis
A severe condition where fluid collects in multiple areas of the baby’s body: abdomen, lungs, skin, and heart.
Intrauterine Growth Restriction (IUGR)
Poor blood and oxygen supply can lead to slow fetal growth.
Preterm Birth or Fetal Death
In severe cases, fluid accumulation may cause very early delivery or, unfortunately, fetal loss.
Postnatal Complications
Some babies may need intensive care or surgery after birth, especially if the heart is significantly affected.
Irregular Heartbeat
The fluid can interfere with the heart’s electrical signals, leading to abnormal heart rhythms.
Amniotic Fluid Imbalance
Heart-related problems can affect kidney function or swallowing, leading to too much or too little amniotic fluid.
Damage to Other Organs
Low oxygen supply may harm the liver, kidneys, or brain.
Placental Dysfunction
When the heart weakens, the placenta may also underperform, affecting the baby’s nutrition.

How to Prevent Fluid Buildup Around the Fetal Heart

While fluid around the fetal heart can happen for various reasons, there are steps you can take to protect yourself and your baby:

Regular Prenatal Checkups
Consistent monitoring with your OB-GYN is crucial to track the baby’s development and catch any issues early.
Manage Chronic Conditions
If you have high blood pressure or diabetes, keep them under control before and during pregnancy to avoid complications.
Prevent Infections
Maintain good hygiene, avoid contact with sick people, and take recommended vaccines like rubella and toxoplasmosis.
Healthy Diet
Eat a balanced diet rich in vitamins and minerals, and take folic acid from the beginning of pregnancy to support fetal health.
Avoid Harmful Substances
Stay away from smoking, alcohol, and medications not prescribed by your doctor.
Genetic Testing When Needed
If you have a family history of genetic disorders, consider early genetic screening to ensure everything is fine.
Control Autoimmune or Hormonal Disorders
Conditions like thyroid issues or autoimmune diseases should be closely monitored during pregnancy.
Rest and Stress Management
Stay calm, avoid stress, and get enough sleep. Mental and physical relaxation benefits both you and your baby.
Extra Care for High-Risk Pregnancies
If you’re pregnant with twins or had previous complications, closer monitoring is necessary.
Limit Physical Strain
Avoid heavy lifting or long standing, as physical stress can affect circulation and harm the baby.
Pediatric Cardiologist Consultation
If there’s a family history of heart problems, an early fetal heart checkup might be advised.
Maintain a Healthy Weight
Try to stay within a healthy weight range during pregnancy, as being underweight or overweight can impact the fetus.
Stay Hydrated
Drink plenty of water throughout the day to help balance body fluids and reduce fluid accumulation risks.
Consult Your Doctor Before Taking Any Medication
Even over-the-counter meds should be approved by your doctor, as some can harm the fetus.
Ensure Placental Health
A well-functioning placenta is essential for nourishing your baby and preventing fluid buildup or other complications.

Treatment of Fluid Accumulation Around the Fetal Heart (Pericardial Effusion): Medications and Surgery

Pericardial effusion in a fetus is a serious condition, and its treatment depends on the underlying cause—not just draining the fluid. Below are the treatment options, whether through medication or surgery:

First: Medication-Based Treatment

In most cases, doctors focus on treating the root cause behind the fluid buildup, since there’s no specific drug to directly remove the fluid around the fetal heart.

1. Treating Infections

If the fluid is caused by a viral or bacterial infection, the mother may be prescribed:

Antibiotics (if it’s a bacterial infection).
Antiviral medications (if it’s a viral infection).

These medications are carefully chosen to be safe for the fetus.

2. Treating Autoimmune Conditions

If the issue is due to the mother’s immune system (like lupus or other autoimmune diseases), the doctor might prescribe:

Steroids (corticosteroids) to reduce inflammation and prevent the immune system from attacking the fetus.

3. Treating Fetal Anemia

In some cases, severe anemia in the fetus (such as from Rh incompatibility) can lead to fluid accumulation. Treatment might include:

Intrauterine blood transfusions to the fetus.
Medications for the mother to improve the fetus’s condition.

4. Medications to Support Fetal Heart Function

If the fetal heart is weak, the doctor might consider:

Medications that enhance heart function, but only under very strict monitoring, since any drug must be safe for the baby.

Second: Surgical or Procedural Treatment

In more critical cases where medication isn’t enough, doctors may resort to surgical intervention:

1. Pericardiocentesis (Draining the Fluid)

A delicate procedure where:

A very thin needle is inserted through the mother’s abdomen.
The excess fluid around the fetal heart is drained using ultrasound guidance.

Purpose: To relieve pressure on the heart and improve its function.
This is done when there is a serious risk to the fetus’s life.

2. Fetal Surgery

If the fluid is caused by a structural heart defect or blood vessel abnormality, doctors may consider:

A highly specialized fetal surgery to correct or repair the issue.
This is rare and only performed in top-level fetal surgery centers by expert teams.

3. Early or Emergency Delivery

If the situation is out of control and the baby needs immediate intervention:

The doctor may decide to deliver the baby early.
The newborn is immediately transferred to neonatal intensive care (NICU) for treatment.

4. Postnatal Treatment

If the baby is born with fluid around the heart or heart complications, they may need:

Surgery after birth, or
Intensive care support until they stabilize.

Which Doctors Handle This Condition?

❤️ 1. Maternal-Fetal Medicine Specialist (MFM)

An OB-GYN who specializes in high-risk pregnancies. They manage cases involving:

Fetal heart or organ issues.
Fluid around the fetal heart.
Fetal growth or structural abnormalities.

They usually make the first diagnosis and decide if surgical or specialist referral is needed.

❤️ 2. Pediatric Cardiologist

If the diagnosis confirms a heart issue (like a congenital defect or weak heart), the case is referred to:

A pediatric cardiologist who specializes in fetal echocardiography.
They perform advanced ultrasounds to thoroughly examine the fetal heart.

❤️ 3. Fetal Surgeon

In rare cases requiring in-womb surgery, a fetal surgeon is brought in:

These procedures are performed only in highly specialized centers.
The medical team works together (MFM specialist + cardiologist + surgeon) to decide the best course of action.