🩸 Anemia in Pregnancy 

🔹 Definition

Anemia in pregnancy is defined by the World Health Organization (WHO) as:

• Hemoglobin (Hb) < 11 g/dL in 1st and 3rd trimesters
• Hb < 10.5 g/dL in 2nd trimester

Severity classification (WHO):

• Mild: Hb 10.0–10.9 g/dL
• Moderate: Hb 7.0–9.9 g/dL
• Severe: Hb < 7.0 g/dL

🔹 Physiological Changes in Pregnancy

• Plasma volume increases by ~50%
• Red cell mass increases by ~20–30%
• Resulting in physiological hemodilution, often referred to as “physiological anemia” of pregnancy

🔹 Etiology

🔸 Nutritional

• Iron deficiency anemia (most common; ~75–90%)
• Folate deficiency
• Vitamin B12 deficiency

🔸 Non-nutritional

• Hemoglobinopathies (e.g., thalassemia, sickle cell disease)
• Aplastic anemia
• Anemia of chronic disease
• Blood loss (e.g., from bleeding piles, antepartum hemorrhage)

🔹 Iron Deficiency Anemia (IDA)

Causes:

• Increased iron demands (~1000 mg total during pregnancy)
• Inadequate intake/absorption
• Parasitic infestations, frequent pregnancies

Investigations:

• Hb, peripheral smear (microcytic hypochromic anemia)
• Serum ferritin (< 15 ng/mL = diagnostic)
• Serum iron, TIBC, transferrin saturation

🔹 Maternal & Fetal Implications

🔸 Maternal:

• Fatigue, palpitations, dyspnea
• Increased risk of infections
• Preeclampsia
• Preterm labor
• Cardiac failure (especially during labor and postpartum)
• Poor wound healing, postpartum hemorrhage (PPH)

🔸 Fetal:

• Intrauterine growth restriction (IUGR)
• Preterm birth
• Low birth weight
• Stillbirth
• Poor iron stores in neonate

🔹 Anesthetic Considerations

🔸 Preoperative Evaluation:

• Full anemia workup
• Cardiorespiratory reserve (CVS exam, ECG)
• Fatigue, palpitations, dyspnea on exertion ,Pallor,wide Pulse Pressure,Tachycardia
• Rule out congestive cardiac failure
• Optimize Hb before elective surgeries or delivery

🔸 During Labor:

• Avoid hypoxia, acidosis, Positional hypotension
• Provide adequate analgesia (e.g., epidural) to reduce oxygen consumption
• Oxygen supplementation
• Avoid conditions which increases Fio2-shivering,fever,Pain,Light plane.
• Blood cross-match and availability
• In sicle cell avoid factors with precipitate Sickling-Hypoxemia,Hypovolemia,Hypotension,Hypoventilation,Hypothermia,acidosis,Light plane

🔸 Regional vs. General Anesthesia:

• Regional anesthesia (epidural/spinal) is preferred if platelet count and hemodynamics are stable, not Preferred in Vitamin b12 deficiency with CNS symptoms  as it worsen Subacute degeneration of spinal cord
• General anesthesia: Used cautiously; rapid desaturation risk; proper preoxygenation and suction ready
• Use N2O cautiously(worsen Vit B12 deficiency)

🔸 Postpartum:

• Monitor for PPH
• Iron therapy continuation
• Evaluate need for blood transfusion

🔹 Management Strategies

🔸 Iron Deficiency Anemia:

• Oral iron: Ferrous sulfate, gluconate, fumarate
• Dose: 100–200 mg elemental iron/day
• Add folic acid: 0.5–1 mg/day
• Parenteral iron: For moderate/severe cases or oral intolerance
• Iron sucrose, ferric carboxymaltose
• Blood transfusion: For Hb <7 g/dL or symptomatic anemia with decompensation

🔸 Folic Acid Deficiency:

• 5 mg/day PO

🔸 Vitamin B12 Deficiency:

• IM injections of hydroxocobalamin

🔹 Prevention (Public Health Perspective)

• WHO recommends daily iron + folic acid supplementation
• 30–60 mg elemental iron + 400 μg folic acid
• Deworming (after 1st trimester)
• Nutritional counseling
• Birth spacing

🔹 MCQs for Practice

1. The most common cause of anemia in pregnancy is:
• A. Aplastic anemia
• B. Iron deficiency anemia ✅
• C. Folate deficiency
• D. Hemolytic anemia

2. Parenteral iron is indicated in all except:

• A. Oral iron intolerance
• B. Non-compliance
• C. Mild anemia in 1st trimester ✅
• D. Imminent delivery

3. Physiological anemia in pregnancy is due to:

• A. Hemolysis
• B. Decreased erythropoietin
• C. Plasma volume increase > RBC mass ✅
• D. Blood loss