Causes of fetal anemia, its types, symptoms and treatment methods

Pregnancy is a journey filled with joy and anticipation, but sometimes mothers face health issues that can affect the baby. One of the most serious conditions is fetal anemia, which occurs when the number of red blood cells in the fetus decreases or hemoglobin levels drop. This affects the oxygen and nutrient supply to all the baby’s organs.This condition can be mild and easily treatable or severe, requiring urgent medical intervention.In this article, we will discuss the causes, types, and symptoms of feta anemia, as well as the best treatment options, including medications, herbal remedies, and suitable exercises. Our goal is to help every mother protect her baby’s health and feel reassured throughout her pregnancy.

Fetal Anemia

Fetal anemia is a condition in which the number of red blood cells or hemoglobin levels in the fetus are lower than normal. This can lead to serious complications if not treated promptly. Hemoglobin is responsible for carrying oxygen to all parts of the body, and when its levels drop, the fetus may become weak and unwell.

Types of Fetal Anemia

Fetal anemia is not a single condition but rather has different types depending on the underlying cause. These types vary in severity and their impact on the baby's health. Let’s explain each type in detail:

1. Immune Hemolytic Anemia (Isoimmune Hemolytic Anemia)

This type occurs when the mother’s immune system attacks the fetus’s red blood cells. It is usually caused by:

Rh incompatibility (Rhesus disease) – when the mother and baby's blood types do not match.
ABO incompatibility – when the mother’s blood type is incompatible with the baby’s.

⚡ How does it happen?

If the mother has a negative Rh factor (-Rh) and the fetus has a positive Rh factor (+Rh), the mother’s body sees the baby’s blood as a foreign substance and produces antibodies that destroy the fetus’s red blood cells.

A similar issue can occur even if the Rh factor is compatible, but the blood types do not match. For example, if the mother has blood type O and the baby has type A or B, the mother’s immune system may still attack the baby's red blood cells.

Complications

Severe anemia
Enlargement of the spleen and liver in the fetus
Hydrops fetalis (fluid accumulation in the fetus)

2. Non-Immune Fetal Anemia

This type is not related to the immune system but occurs due to other factors, including:

A) Anemia Caused by Viral Infections

Some viruses can damage the fetal bone marrow, preventing the production of red blood cells. The most common viruses responsible for this condition include:

Parvovirus B19 (which causes "fifth disease")
Cytomegalovirus (CMV)
Rubella virus

???? Complications

Bone marrow failure, leading to a lack of red blood cell production
Severe oxygen deficiency in the fetus
Impaired growth and development

B) Anemia Due to Intrauterine Bleeding

If the fetus loses a significant amount of blood due to internal bleeding, severe anemia can occur. This bleeding may result from:

Feto-maternal hemorrhage (when blood leaks from the fetus into the mother's circulation)
Placental or umbilical cord abnormalities

⚠️ Complications

Severe drop in fetal blood pressure
Oxygen deficiency
Fetal death in severe cases

C) Genetic Anemia

Certain inherited disorders can lead to reduced hemoglobin production or increased red blood cell destruction, such as:

Thalassemia – a genetic disorder affecting hemoglobin production
Sickle cell anemia – where red blood cells are misshapen and break down quickly
Mediterranean anemia (Beta-Thalassemia) – causes inadequate hemoglobin production

???? Complications

Poor fetal growth
Need for frequent blood transfusions after birth

3. Anemia Due to Nutritional Deficiencies

If the mother has a severe deficiency in iron, folic acid, or vitamin B12, the fetus may not be able to produce enough red blood cells.

This type is more common in mothers with malnutrition or anemia during pregnancy.

????️ Complications

Intrauterine growth restriction (IUGR)
Reduced fetal activity due to lack of oxygen

Age Groups Most at Risk for Fetal Anemia

Fetal anemia occurs in unborn babies during pregnancy, meaning it is related to the fetus's gestational age rather than the age of children or adults. However, certain stages of pregnancy make the fetus more vulnerable to developing anemia.

1. First Trimester (Months 1-3)

Fetal anemia is rare during this stage but can occur if:

The mother contracts a viral infection such as Parvovirus B19.
There is a family history of genetic blood disorders like thalassemia or sickle cell anemia.

2. Second Trimester (Months 4-6)

This is the period when fetal anemia most commonly begins to appear, especially due to:

Blood type incompatibility between the mother and fetus, as maternal antibodies start attacking fetal red blood cells.
Viral infections affecting the fetus’s bone marrow.
Placental abnormalities or intrauterine bleeding.

3. Third Trimester (Months 7-9)

This is the most critical period for fetal anemia, as the baby requires more oxygen for growth. Severe anemia at this stage can lead to:

Enlargement of the spleen and liver due to increased red blood cell destruction.
Hydrops fetalis (fluid accumulation in the fetus).
Severe oxygen deficiency, which can cause serious complications or even fetal death if untreated.

Which Mothers Are at Higher Risk of Having a Baby with Fetal Anemia?

Certain mothers are more likely to have a baby with fetal anemia, including:

Mothers under 20 years old – due to nutritional deficiencies or lack of proper prenatal care.
Mothers over 35 years old – as they have a higher risk of health conditions like diabetes or hypertension, which can affect the baby’s health.
Mothers with a history of anemia or thalassemia.
Mothers who have previously had a baby with immune-related fetal anemia.

Causes of Fetal Anemia

Fetal anemia can result from various factors, some related to immune system disorders and others due to genetic conditions or infections. The main causes include:

1. Blood Type Incompatibility (Rh Disease - Rh Incompatibility)

This occurs when the mother has a negative Rh factor (-Rh) while the fetus has a positive Rh factor (+Rh).

The mother's immune system recognizes the baby’s red blood cells as foreign and produces antibodies that attack and destroy them, leading to anemia.
This condition is more common in the second pregnancy, as the mother’s body has already developed antibodies from the first pregnancy.

2. Viral and Bacterial Infections

Certain infections can damage or reduce the production of red blood cells in the fetus, including:

Parvovirus B19 – prevents the bone marrow from producing red blood cells.
Rubella virus – can cause severe blood disorders in the fetus.
Cytomegalovirus (CMV) – affects the bone marrow and spleen, leading to anemia.
Syphilis infection – may cause red blood cell destruction in the fetus.

3. Genetic Disorders Affecting Hemoglobin Production

Some inherited conditions interfere with hemoglobin production or increase red blood cell breakdown, such as:

Thalassemia – a genetic disorder that disrupts hemoglobin formation, leading to rapid red blood cell destruction.
Sickle cell anemia – causes abnormally shaped red blood cells that break down quickly.
Mediterranean anemia (Beta-Thalassemia) – leads to reduced hemoglobin production and fetal anemia.

4. Intrauterine Bleeding or Fetal Blood Loss

Placental or umbilical cord bleeding can cause severe fetal blood loss.
Feto-maternal hemorrhage – where fetal blood leaks into the mother’s circulation, reducing fetal blood volume.
Twin-to-Twin Transfusion Syndrome (TTTS) – in twin pregnancies, one twin may receive more blood than the other, leading to severe anemia in the deprived twin.

5. Autoimmune Diseases Attacking Fetal Red Blood Cells

Certain rare conditions cause the mother's immune system to attack the fetus’s red blood cells, even if their blood types are compatible.

Autoimmune diseases like Lupus (SLE) or Antiphospholipid Syndrome can affect blood flow to the fetus and contribute to anemia.

6. Maternal Nutritional Deficiencies

If the mother lacks essential nutrients such as:

Iron
Folic acid
Vitamin B12

This can lead to fetal anemia, as the baby does not receive the necessary components to produce red blood cells. Poor maternal nutrition during pregnancy affects overall fetal growth, including blood health.

7. Spleen and Liver Disorders in the Fetus

The spleen is responsible for breaking down old red blood cells. If it enlarges, it may destroy too many cells too quickly.
Liver diseases, whether genetic or infection-related, can interfere with hemoglobin production, leading to anemia.

8. Exposure to Toxic Substances and Harmful Medications

Some medications (e.g., chemotherapy drugs or strong antibiotics) can impair red blood cell production.
Exposure to toxins such as lead or pesticides can negatively impact fetal blood formation.

Diagnosis of Fetal Anemia

To determine if a fetus has anemia, doctors use several diagnostic methods, including:

1. Ultrasound (Sonography)

Detects signs of hydrops fetalis (fluid accumulation in the fetus) or increased amniotic fluid levels (polyhydramnios).

2. Doppler Ultrasound on the Middle Cerebral Artery (MCA Doppler Scan)

Measures blood flow velocity in the fetal brain.
Increased velocity suggests anemia because less viscous blood moves faster.

3. Maternal Blood Tests

Can identify immune reactions against fetal red blood cells (e.g., Rh incompatibility).

4. Umbilical Cord Blood Sampling (Cordocentesis)

The most accurate test for fetal anemia.
Involves drawing a blood sample from the umbilical cord to check hemoglobin levels and red blood cell count.

Symptoms of Fetal Anemia

Fetal anemia affects the baby inside the womb, but mothers do not directly feel its symptoms. Instead, doctors detect the condition through medical examinations. However, some signs may indicate a potential problem.

1. Symptoms Observed in the Fetus

A) Decreased Fetal Movement

Anemic fetuses receive less oxygen, leading to reduced activity.
If the mother notices less movement than usual, she should inform the doctor immediately.

B) Fetal Swelling or Hydrops Fetalis

Severe anemia reduces oxygen supply, making the heart work harder.
Excess strain on the heart causes fluid accumulation in the abdomen, chest, or under the skin.

C) Enlarged Liver and Spleen

The liver and spleen work harder to compensate for the lack of red blood cells, causing organ enlargement.

D) Excess Amniotic Fluid (Polyhydramnios)

Oxygen deficiency disrupts the fetus’s ability to swallow amniotic fluid, leading to fluid buildup.

E) Rapid Fetal Heartbeat (Fetal Tachycardia)

The heart beats faster to compensate for low oxygen levels.
Doctors may notice abnormally high fetal heart rates during ultrasound scans.

2. Symptoms Detected in Medical Examinations

A) Increased Blood Flow Velocity in the Middle Cerebral Artery (MCA Doppler Scan)

Anemia makes blood less viscous, causing faster circulation in the brain’s arteries.
High MCA velocity is a strong indicator of fetal anemia.

B) Low Hemoglobin Levels in Cordocentesis

If hemoglobin levels are below normal, the fetus is diagnosed with anemia.

C) Abnormal Maternal Blood Test Results

If the cause is Rh incompatibility, maternal blood tests may show antibodies attacking fetal red blood cells.

3. Symptoms the Mother May Experience

Although mothers don’t directly feel fetal anemia, they may notice:

Unusual abdominal enlargement due to hydrops fetalis or excess amniotic fluid.
Reduced fetal movement or activity.
A heavy or pressured sensation in the uterus, especially if fetal swelling occurs.

Medical Treatment for Fetal Anemia

The treatment of fetal anemia depends on its cause and severity. Mild cases may only require close monitoring, but moderate to severe cases often need medications or medical interventions.

1. Medications for Immune-Related Fetal Anemia (Rh Incompatibility)

A) RhoGAM Injection (Anti-D Immunoglobulin)

The primary treatment for Rh incompatibility.
Given as an injection at the 28th week of pregnancy.
Additional doses are required if there is bleeding or a previous miscarriage.
Prevents the mother's immune system from producing antibodies that attack the baby's red blood cells.

2. Medications for Virus-Induced Fetal Anemia

If anemia is caused by a viral infection like Parvovirus B19 or Cytomegalovirus (CMV), there is no direct cure, but doctors may use:

Corticosteroids:
- Boost the mother’s immune system.
- Reduce inflammation and immune reactions against fetal red blood cells.
Antiviral Medications (in some cases):
- Not all viruses have effective treatments during pregnancy.

3. Medications to Treat Nutritional Deficiencies

If fetal anemia is due to iron, folic acid, or vitamin B12 deficiency, the mother may need:

Iron Supplements (Ferrous sulfate).
Folic Acid to support red blood cell production.
Vitamin B12 if there is a deficiency.

???? Note: While supplements help prevent anemia, they are not sufficient for treating severe cases.

4. Medications to Improve Placental Blood Flow

Doctors may prescribe medications to enhance blood circulation to the fetus, including:

Low-dose Aspirin:
- Improves placental function.
Heparin (Blood Thinner):
- Used if the mother has a blood clotting disorder affecting fetal blood supply.

Treatment for Severe Cases

If fetal anemia is severe, medications alone are not enough, and doctors may resort to:

Intrauterine Blood Transfusion (IUT):
- Direct blood transfusion to the fetus through the umbilical cord.
Early Delivery:
- If the condition is critical and waiting poses a risk, labor may be induced.

Treating Fetal Anemia with Herbs: Is It Possible?

It is very important to understand that fetal anemia is a serious medical condition, and relying solely on herbs for treatment is not advisable. The primary treatment must be under medical supervision. However, some herbs and natural supplements may help the mother improve her health and support the baby, especially if the anemia is due to iron or vitamin deficiency in the mother.

1. Iron-rich herbs for treating anemia in mothers

These herbs help increase iron levels and hemoglobin in the mother's blood, which may reduce the risk of fetal anemia:

Fenugreek
- Rich in iron and helps in red blood cell production.
- Can be consumed as a tea or added to food.
Spinach and Arugula
- High in iron and folic acid, essential for blood cell production.
- Can be added to salads or blended into juice with orange for better iron absorption.
Parsley
- Contains a good amount of iron and aids in iron absorption.
- Can be consumed as a tea or added to meals.
Beetroot (Beets)
- Rich in iron and folic acid, which help improve hemoglobin levels.
- Can be eaten or consumed as juice with carrots.

2. Herbs that enhance iron absorption in mothers

Some herbs help the body absorb iron more efficiently, such as:

Lemon and Orange
- Vitamin C boosts iron absorption from food.
- Best consumed as juice along with iron-rich meals.
Ginger
- Helps improve blood circulation, which may aid in oxygen transport to the baby.
- Can be consumed with honey and lemon.

3. Herbs for improving placental health and fetal blood circulation

Certain herbs help enhance blood flow to the placenta, reducing the risk of oxygen deficiency in the baby:

Cinnamon
- Improves blood circulation in the mother but should be consumed in small amounts during pregnancy.
Green Tea
- Contains antioxidants that support blood vessel health, but excessive consumption may reduce iron absorption.
Coconut Water
- Helps with hydration and blood flow improvement, reducing the risk of dehydration-related placental issues.

⚠ Important Warnings Before Using Herbs

Not all herbs are safe during pregnancy, and some may cause complications if consumed in large amounts, such as:

Cinnamon and Ginger: Should be taken in very moderate amounts.
Green Tea: Excessive consumption can inhibit iron absorption.
Fenugreek: Beneficial, but excessive intake may cause uterine contractions.

Can Exercise Help Treat Fetal Anemia?

Exercise is not a direct treatment for fetal anemia, but it can support the mother's health by improving blood flow and oxygen delivery to the baby, which may help reduce complications.

Light exercises can help:

Improve the mother's blood circulation, ensuring better oxygen transport to the fetus.
Enhance iron absorption and stimulate red blood cell production.
Reduce stress, which can impact placental blood flow.
Decrease fluid retention, which may occur in cases of fetal hydrops.

Best Exercises to Support Fetal Anemia Treatment and Maternal Health

1. Daily Walking ????‍♀️

Walk for 20-30 minutes daily in an open space or on a treadmill.
Helps improve circulation and ensures better oxygen delivery to the baby.

2. Deep Breathing Exercises ????

Inhale deeply through the nose, hold for a few seconds, then exhale slowly through the mouth.
Repeat 5-10 times daily to enhance oxygen flow.

3. Light Stretching (Stretching Exercises) ????‍♀️

Simple leg and arm stretches to boost circulation without excessive effort.
Can be done for 5-10 minutes daily.

4. Prenatal Yoga ????‍♀️

Simple poses like the butterfly pose or seated deep breathing help improve blood flow.
Recommended twice a week.

5. Light Swimming ????‍♀️

One of the best exercises for circulation without adding pressure on the body.
Can be done once or twice a week.

⚠ Exercises to Avoid During Fetal Anemia

Strenuous or high-impact exercises can be risky, such as:

Strength training & weightlifting ????️‍♀️
Long-distance running ????
Exercises involving jumping or abdominal pressure

Which Doctor Treats Fetal Anemia?

The primary specialist for fetal anemia is an Obstetrician & Gynecologist (OB/GYN). However, in severe or high-risk cases, a Maternal-Fetal Medicine Specialist (MFM) is consulted.

Mild cases: Managed by a regular OB/GYN.
Severe cases (requiring fetal blood transfusions or specialized interventions): Referred to an MFM specialist.