Anemia In Pregnancy : Signs and symptoms, Cause, treatment......

Normally during pregnancy, erythroid hyperplasia of the marrow occurs, and RBC mass increases. However, a disproportionate increase in plasma volume results in hemodilution (hydremia of pregnancy): Hct decreases from between 38 and 45% in healthy women who are not pregnant to about 34% during late single pregnancy and to 30% during late multifetal pregnancy. Thus during pregnancy, anemia is defined as Hb < 10 g/dL (Hct < 30%). If Hb is < 11.5 g/dL at the onset of pregnancy, women may be treated prophylactically because subsequent hemodilution usually reduces Hb to < 10 g/dL. Despite hemodilution, oxygen-carrying capacity remains normal throughout pregnancy. Hct normally increases immediately after birth.

Anemia occurs in up to one third of women during the 3rd trimester. The most common causes are

• Iron deficiency
• Folate deficiency

Symptoms and Signs

Early symptoms of anemia are usually nonexistent or nonspecific (eg, fatigue, weakness, light-headedness, mild dyspnea during exertion). Other symptoms and signs may include pallor and, if anemia is severe, tachycardia or hypotension.

Anemia increases risk of

• Preterm delivery
• Postpartum maternal infections

Diagnosis

• CBC, followed by testing based on MCV value

Diagnosis of anemia begins with CBC; usually, if women have anemia, subsequent testing is based on whether the MCV is low (< 79 fL) or high (> 100 fL):

• For microcytic anemias: Evaluation includes testing for iron deficiency (measuring serum ferritin) and hemoglobinopathies (using hemoglobin electrophoresis). If these tests are nondiagnostic and there is no response to empiric treatment, consultation with a hematologist is usually warranted.
• For macrocytic anemias: Evaluation includes serum folate and B12 levels.
• For anemia with mixed causes: Evaluation for both types is required.

Treatment

• Treatment to reverse the anemia
• Transfusion as needed for severe symptoms

Treatment of anemia during pregnancy is directed at reversing the anemia (see below).

Transfusion is usually indicated for any anemia if severe constitutional symptoms (eg, light-headedness, weakness, fatigue) or cardiopulmonary symptoms or signs (eg, dyspnea, tachycardia, tachypnea) are present; the decision is not based on the Hct.