Hemolytic Disease of the Newborn

Hemolytic disease of the newborn (also called erythroblastosis fetalis, and in severe cases, hydrops fetalis) results when IgG antibodies are produced in the mother that react against Rh or ABO antigens on fetal red cells. This results in fetal anemia, decreased oncotic pressure with fetal edema, and increased fetal bilirubin leading to kernicterus. Severe cases may produce fetal death.

A complete treatment of HDN is beyond the scope of this lesson. In cases where there is a known blood type incompatibility or previous history of HDN, maternal antibody titres (Rh, or anti-A or -B in an O-type mother) are followed and rising titres trigger additional testing.

The risk of HDN in utero can be estimated by measuring amniotic fluid bilirubin in specimens obtained by amniocentesis. In high-risk cases, serial specimens are followed over time. If bilirubin rises above established reference values, delivery is induced prematurely (if the pregnancy is at 32 weeks or later), or intrauterine exchange transfusion can be attempted.

Congenital Diseases

Fetal/Placental Viability

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Last modified: 1/22/97; Author: J. Harrison