1. Rh(D) Alloimmunization

2. Prevention of Rh(D) alloimmunization in pregnancy
Rh(D)-negative pregnant women
Exposed to fetal D-positive red cells are at risk for developing anti-D antibodies.
Widespread use of anti-D immunoglobulin has dramatically reduced, but not eliminated, D alloimmunization.

3. Prevention of Rh(D) alloimmunization in pregnancy
Hemolytic disease of the fetus and newborn
Severe form of anemia caused by the production of maternal antibodies against fetal red blood cells.
Rhesus D (RhD), ABO, and less commonly other blood group antigen incompatibility between the fetus/infant and the mother can lead to the production of maternal antibodies (alloimmunization) when there is fetomaternal hemorrhage

4. Evaluation Screening First-time alloimmunized pregnancies
Blood antigen typing for ABO and Rhesus D (RhD) groups and maternal Rh antibody
At the first prenatal visit.
First-time alloimmunized pregnancies
Monitor every 4 weeks
Increased risk for hemolytic anemia.
Pregnancies in women that were previously Rh alloimmunized
Increase the risk for hemolytic anemia in the infant.

5. Management Pregnant Rh-negative women with
a negative maternal Rh antibody screening result,
indicating no prior anti-D alloimmunization,
should have a repeat screening at 28 weeks to assess for alloimmunization
if it is negative should receive 300 mcg Rh immune globulin intramuscularly, with consideration of a second dose if the fetus has not delivered by 40 weeks gestation
positive maternal Rh antibody screening result,
indicating an RhD sensitized pregnancy, require determination of maternal RhD antibody titers

6. Prevention of Rh(D) alloimmunization in pregnancy
Rh(D)-negative Pregnants whose fetus is/may Rh(D)-positive:
Administration of anti-D immunoglobulin early in the third trimester
300 micrograms at 28 weeks of gestation
100 to 120 micrograms at 28 and 34 weeks

7. Management Management of Rh alloimmunized fetus may include:
Intrauterine transfusion for fetal hematocrit ≤ 30% before 35 weeks gestation
Testing for fetal lung maturity and amniotic bilirubin level
Guide the decision as to when and if labor should be induced

8. Prevention of Rh(D) alloimmunization in pregnancy
Antenatal anti-D immunoglobulin
300 micrograms as soon as possible within 72 hours of the event
Increased risk of fetomaternal hemorrhage
ectopic pregnancy,
miscarriage,
abortion,
multifetal reduction,
amniocentesis,
chorionic villus sampling,
blunt abdominal trauma,
external cephalic version,
antepartum bleeding, and
fetal death.

9. Prevention of Rh(D) alloimmunization in pregnancy
Ongoing risk for fetomaternal hemorrhage
Repeat dosing
chronic placental abruption or placenta previa with intermittent vaginal bleeding
Serial determinations of the maternal indirect Coombs every three weeks with repeat dosing if it is found to be negative.

11. Prevention of Rh(D) alloimmunization in pregnancy
Anti-D immunoglobulin within 72 hours of delivery of an Rh(D)- positive infant
300 micrograms
Additional doses
Excessive fetomaternal hemorrhage
If inadvertently omitted after delivery
as soon as possible
Partial protection is afforded with administration within 13 days of the birth
May be an effect as late as 28 days after delivery

12. Prevention of Rh(D) alloimmunization in pregnancy
Management of pregnancies complicated by alloimmunization
intrauterine fetal transfusions
Investigational
maternal plasmapheresis
intravenous immune globulin therapy