Makindo Medical Notes.com

Introduction

• Anaemia in pregnancy is defined as a haemoglobin (Hb) level of less than 11 g/dL in the first and third trimesters, and less than 10.5 g/dL in the second trimester.
• It occurs when the body doesn’t have enough healthy red blood cells to carry adequate oxygen to tissues.

Epidemiology

• Anaemia is one of the most common medical conditions in pregnancy, affecting nearly 41.8% of pregnant women globally, according to WHO.
• It is more common in developing countries due to malnutrition and higher rates of infections.

Causes

• The most common cause of anaemia in pregnancy is iron deficiency, due to the increased demand for iron to support fetal development and the expansion of maternal blood volume.
• During pregnancy, blood volume increases by about 30-50%, which causes a dilutional effect, lowering hemoglobin concentration. This is termed physiological anaemia or dilutional anaemia, and it is more pronounced in the second trimester.
• Other causes include folate deficiency, vitamin B12 deficiency, haemolytic anaemia (e.g., sickle cell disease, thalassemia), and anaemia of chronic disease.

Risk factors

• Poor nutritional intake (low iron, folate, and B12)
• Multiple pregnancies (increased demand for nutrients)
• Chronic infections (e.g., malaria, HIV, or tuberculosis)
• Short intervals between pregnancies
• Heavy menstrual bleeding prior to pregnancy, which may deplete iron stores
• Pre-existing anaemia or malabsorption disorders (e.g., coeliac disease)

Complications

• Maternal: Severe anaemia is associated with increased risk of preterm birth, low birth weight, placental abruption, and maternal morbidity such as heart failure or infection.
• Fetal Complications: Anaemia increases the risk of fetal growth restriction, low birth weight, preterm birth, and even fetal mortality in severe cases. Poor oxygen delivery to the fetus can also impair brain development.

Prevention

• Encourage to iron-rich foods such as red meat, poultry, fish, legumes, and fortified cereals.
• Adequate intake of folate-rich foods (leafy greens, citrus fruits) and vitamin B12 (meat, dairy products) is also essential.
• Routine iron and folic acid supplementation is recommended during pregnancy to prevent anaemia. WHO recommends daily iron (30-60 mg) and folic acid (400 mcg) supplements during pregnancy.
• Haemoglobin levels are typically checked during the first prenatal visit and again in the second and third trimesters to ensure early detection and management of anaemia.