Normocytic anaemia is when people have red blood cells that are of standard size and shape, and normal haemoglobin concentrations, but continue to suffer from anaemia.¹ The mean corpuscular volume (MCV), which measures the average size of red blood cells, in normocytic anaemia is within the normative range of 80-100 fL. Often, the main aetiology (cause) of normochromic normocytic anaemia is a chronic disease. The incidence of anaemia attributable to chronic illnesses varies based on the particular condition: infections range from 18% to 95%, cancers from 30% to 77%, autoimmune disorders from 8% to 71%, and chronic renal disease and inflammation from 23% to 50%.²

Understanding the aetiology, related hazards, and therapy approaches for normocytic anaemia during pregnancy is essential for safeguarding maternal health and achieving ideal pregnancy results.

Causes of normocytic anaemia in pregnancy

Normocytic anaemia in pregnancy can be physiological or pathological:³

Physiological (dilutional) anaemia 

During pregnancy, a woman’s plasma volume increases by up to 50%, while red blood cell mass increases only by about 25–30%. This discrepancy results in haemodilution, a condition commonly referred to as physiological anaemia of pregnancy. It typically presents in the second trimester and is usually normocytic.

Anaemia of chronic disease (ACD)

ACD, or anaemia of inflammation, is common in women with underlying chronic infections, autoimmune disorders, diabetes, or malignancies. Inflammatory cytokines interfere with iron metabolism, reduce erythropoietin response, and suppress bone marrow activity, resulting in normocytic anaemia.

Acute or chronic blood loss

Conditions such as placenta praevia, placental abruption, uterine rupture, or even undiagnosed gastrointestinal bleeding can result in normocytic anaemia due to the rapid or sustained loss of red cells, which outcompetes the bone marrow’s ability to respond with immature cells. This causes macrocytosis, where the cells are larger than normal.

Haemolytic anaemia

Autoimmune conditions (such as autoimmune haemolytic anaemia), inherited disorders (e.g. sickle cell disease), or pregnancy-specific complications like HELLP syndrome (Hemolysis, Elevated Liver enzymes, Low Platelet count) can lead to increased destruction of red blood cells, resulting in normocytic anaemia.

Bone marrow suppression

Diseases like aplastic anaemia, leukaemia, or myelodysplastic syndromes, and exposure to certain medications or chemotherapy agents can impair the bone marrow’s ability to produce red cells, resulting in normocytic anaemia.

Early iron deficiency

In the early stages of iron deficiency, red blood cells may still be normocytic before becoming microcytic (smaller than usual) as the condition progresses. Thus, normocytic anaemia could represent a transitional phase in developing iron deficiency.

Risks and complications

Normocytic anaemia, if unrecognised or untreated, may pose several maternal and foetal risks:⁴

Maternal risks

•  Fatigue, weakness, and reduced physical performance
• Increased risk of postpartum haemorrhage and infections
• Poor tolerance to blood loss during delivery or surgery

Foetal risks

• Low birth weight and intrauterine growth restriction (IUGR)
• Increased risk of preterm birth.
• Impaired placental function and oxygen delivery to the foetus
• Long-term consequences such as developmental delays or neonatal anaemia

Diagnosis

Fatigue, pallor, breathlessness, and reduced exercise tolerance may be present but are often mistaken for normal pregnancy symptoms.⁵ Diagnosis is as follows:

• Complete Blood Count (CBC): Low haemoglobin with normal MCV and often normal MCH (mean corpuscular haemoglobin).
• Reticulocyte Count: To assess marrow response (low in bone marrow suppression, high in hemolysis)
• Iron Studies: To rule out early iron deficiency—includes serum ferritin, transferrin saturation, and serum iron
• Vitamin B12 and Folate Levels: To rule out macrocytic anaemias
• Renal and Liver Function Tests: Especially if HELLP syndrome or chronic disease is suspected
• Peripheral Blood Smear: Can provide visual clues to haemolysis, marrow suppression, or abnormal cell morphology
• Inflammatory Markers: CRP (C-reactive protein) or ESR (erythrocyte sedimentation rate) to support a diagnosis of anaemia of chronic disease

Management strategies

The treatment of normocytic anaemia in pregnancy depends on identifying and addressing the underlying cause:⁶

Physiological anaemia

• No specific treatment: reassurance and monitoring
• Emphasise adequate nutrition and prenatal vitamins

Iron supplementation

• Even in normocytic anaemia, empirical iron therapy is often initiated while waiting for lab results
•  Oral or intravenous iron may be used depending on tolerance and severity

Treatment of underlying disorders

• Chronic diseases should be managed in collaboration with specialists
• Autoimmune conditions, infections, or renal disease may require immunomodulators or antibiotics

Transfusion

Performed in severe symptomatic anaemia cases, especially near delivery or in cases of acute blood loss.

Monitoring

• Regular haemoglobin checks during antenatal visits
• Close follow-up in high-risk pregnancies with known chronic illnesses or prior history of anaemia

FAQs

What is normocytic anaemia, and how is it different from other types of anaemia?

Normocytic anaemia is a condition in which the red blood cells are normal in size (indicated by a normal mean corpuscular volume or MCV), but their overall number or haemoglobin content is reduced, resulting in decreased oxygen delivery to the body’s tissues. Unlike microcytic anaemia, which involves smaller-than-normal red blood cells (commonly due to iron deficiency), or macrocytic anaemia, where red blood cells are abnormally large (often caused by vitamin B12 or folate deficiency), normocytic anaemia presents with red cells of typical size but insufficient quantity or function.

Is normocytic anaemia common in pregnancy?

Yes, normocytic anaemia is quite common in pregnancy, especially in the second and third trimesters, primarily due to physiological haemodilution, where the plasma volume increases more rapidly than the red blood cell mass. While this dilutional anaemia is typically benign and expected during pregnancy, normocytic anaemia can also arise from underlying pathological conditions such as chronic diseases, haemolysis, or acute blood loss, and therefore warrants thorough evaluation.

What are the main causes of normocytic anaemia during pregnancy?

The causes of normocytic anaemia in pregnancy vary widely. The most frequent is physiological anaemia, which is part of the body’s natural adaptation to pregnancy. However, more concerning causes include anemia of chronic disease (related to infections, autoimmune disorders, or kidney issues), acute or chronic blood loss (such as from placental complications), haemolytic anemia (including sickle cell disease or HELLP syndrome), bone marrow suppression (from conditions like aplastic anemia or leukemia), and early-stage iron deficiency before red cell size becomes affected.

What are the symptoms of normocytic anaemia in pregnancy?

Symptoms of normocytic anaemia can be subtle and often overlap with normal pregnancy experiences, which makes diagnosis challenging. Common symptoms include persistent fatigue, generalised weakness, pale skin, shortness of breath on exertion, dizziness, lightheadedness, and occasionally a rapid heartbeat. Because many of these symptoms are nonspecific, blood tests are essential for accurate diagnosis.

How is normocytic anaemia diagnosed?

Normocytic anaemia is diagnosed through a combination of clinical evaluation and laboratory investigations. A complete blood count (CBC) is the starting point, revealing low haemoglobin levels with normal MCV. Further tests may include reticulocyte count to evaluate bone marrow activity, iron studies to rule out iron deficiency, vitamin B12 and folate levels, liver and kidney function tests, inflammatory markers, and a peripheral blood smear to look for any abnormal cell shapes or signs of hemolysis.

Can normocytic anaemia harm the baby?

Yes, untreated normocytic anaemia can pose risks to the developing fetus. It can lead to low birth weight, intrauterine growth restriction, preterm birth, and in some cases, developmental delays. In severe cases, poor oxygenation may impair placental function, and the baby may also be born with anaemia or have trouble adapting to extrauterine life. Therefore, prompt management is essential to prevent these complications.

How is normocytic anaemia treated during pregnancy?

The treatment of normocytic anaemia during pregnancy is tailored to its cause. Physiological anaemia typically requires no intervention beyond continued prenatal supplementation and proper nutrition. If early iron deficiency is suspected, oral or intravenous iron therapy may be initiated. In cases of chronic disease-related anaemia, the focus shifts to treating the underlying condition. Haemolytic anaemia may require steroids, folic acid supplementation, or transfusions, while bone marrow suppression demands specialist care. Severe cases with symptomatic anaemia or acute blood loss may necessitate blood transfusion.

Summary

Normocytic anaemia in pregnancy is characterised by a normal red blood cell size (MCV 80–100 fL) but reduced haemoglobin levels. It can be physiological—mainly due to haemodilution during pregnancy—or pathological, stemming from chronic diseases, blood loss, haemolysis, bone marrow suppression, or early-stage iron deficiency.

Key Causes:

• Physiological (dilutional) anaemia from increased plasma volume
• Anaemia of chronic disease (ACD) from infections, autoimmune disorders, or chronic inflammation
• Acute/chronic blood loss, including obstetric and gastrointestinal sources
• Haemolytic anaemia, e.g., sickle cell disease, HELLP syndrome
• Bone marrow suppression or early iron deficiency

Risks:
Untreated, normocytic anaemia increases risks of fatigue, infections, and poor delivery outcomes for mothers, and may lead to low birth weight, preterm birth, or developmental delays in infants.

Diagnosis:
Relies on clinical signs and lab tests, including CBC, iron studies, vitamin B12/folate levels, reticulocyte count, and inflammatory markers.

Management:
Treatment is cause-specific, ranging from reassurance for physiological anaemia to iron supplementation, chronic disease management, or transfusions in severe cases. Regular monitoring throughout pregnancy is essential for early detection and intervention.

Early identification and targeted management are vital to ensure healthy maternal and fetal outcomes.