Hemolytic Diseases of the Newborn occur when maternal antibodies are present naturally or form in response to an antigen from the fetal blood crossing the placenta and entering the maternal circulation. Maternal antibodies of the immunoglobulin G (IgG) class, in turn, cross the placenta, causing hemolysis of the fetal red blood cells (RBCs), resulting in possible hyperbilirubinemia, jaundice, and anemia.Hemolytic disease of the newborn occurs most often when the blood groups of the mother and baby are different.The most common cause of hemolytic disease of the fetus and newborn is ABO incompatibility, followed by Rh(D) incompatibility.

Other Causes of Hemolysis

• Glucose-6-phosphate dehydrogenase (G6PD) deficiency

• Galactosemia

• Crigler-Najjar disease

• Hypothyroidism

• Gilbert syndrome

• Pyruvate kinase deficiency

• Spherocytosis

Nursing Care

Events that can cause a woman to develop antibodies to the Rh factor:

• Previous pregnancy with an Rh-positive fetus

• Transfusion with Rh-positive blood, which causes immediate sensitization

• Ectopic pregnancy, miscarriage, or induced abortion after 8 or more weeks of gestation or fetal death at any time

• Chorionic villus sampling or amniocentesis

• Placental abruption

• External cephalic version

• Trauma

The nurse checks the woman's medical record to determine whether she has received Rh immune globulin. For an Rh-negative pregnant woman, the risk of the fetus being Rh-positive must be determined. The first assessment is a paternal zygosity test to determine the father's Rh factor. If the father is Rh-positive, the infant is more likely Rh-positive. An indirect Coombs test is repeated at 28 weeks. If the result remains negative, the woman is given an intramuscular injection of Rho(D) immune globulin. If the result is positive, the injection is repeated every 2 to 4 weeks to monitor the maternal antibody titer until a critical value is reached. Once a critical value is noted, an assessment of fetal hemolytic process is needed.