Rh Incompatability

Rh Incompatibility

Occurs when the mother and fetus have opposite Rh antibodies. So the fetus body reacts as if it was an invasive substance. This an become a threat in the second pregnancy.

Erythroblastosis Fetalis

• Since the Rh factor exists as a portion of the red blood cell, they can cross the placenta and cause hemolysis or the destruction of red blood cells of the fetus.

• This process of hemolysis can cause the fetus to be so deficient in red blood cells that not enough oxygen is transported to their body cells

• Other names: Hemolytic disease of the newborn, hemolytic anemia

Assessment

• Rh-negative mothers should have anti-D antibody titer done at a first pregnancy visit. It is repeated at week 28 of pregnancy

• normal titer results = 0, minimal = 1:8, A titer result of normal or minimal on both visits would require no therapy.

• If elevated (1:16 or greater) at first assessment, fetus will be monitored every 2 weeks to predict when anemia is present or fetal red blood cells are being destroyed.

Therapeutic Management

• RhIG (RhoGAM), a commercial preparation of passive Rh (D) antibodies against the Rh factor is administered at 28 weeks of pregnancy to reduce the total number of maternal antibodies being formed.

• Given again by injection to the mother in the first 72 hours after birth of an Rh-positive child to further prevent the woman from forming natural antibodies.

• After birth, the infant's blood type will be determined from a sample of the cord blood. If it is Rh positive, the mother will receive the RhiG injection.

Intrauterine Transfusion

• Red blood cells can be injected directly into a vessel in the fetal cord using amniocentesis technique to restore fetal red blood cells destroyed due to Rh incompatibility.

• After birth, the infant may require phototherapy lights to reduce bilirubin levels released from the destroyed red blood cells or an exchange transfusion to remove hemolyzed red blood cells and replace them with healthy blood cells.

Rh-negative mother + Rh-positive baby =

Rh Incompatibility

Rh Incompatibility =

Hemolytic anemia for the baby

Left untreated Rh Incompatibility =

Harder following pregnancies due to the large amount of anitbodies that the Rh-negative mother has produced.