Rh Incompatibility in Pregnancy. Rh incompatibility occurs when a pregnant woman whose blood type is Rh-negative is exposed to Rh-positive blood from her fetus, leading to the mother's development of Rh antibodies

1. Rh –Incompatibility in Pregnancy
Mukesh Sah
Post graduate Medical Intern

2. Rhesus Incompatibility

3. Rh Incompatibility
The Rh factor is a specific protein found on the surface of red blood
cell
When a mother and her unborn baby carry different Rh protein
factors, their condition is called Rh incompatibility.
If the pregnant women and her husband are Rh negative, there is no
reason to worry about Rh incompatibility.

4. Rh Incompatibility
If she is Rh negative and her husband is Rh
positive, the baby will inherit the father’s blood
type, creating incompatibility between mother and
her fetus.
Rh factor doesn’t directly affect health. However,
Rh factor becomes important during pregnancy. If a
woman is Rh-negative and her baby is Rh-positive,
then her body will approach the Rh-positive protein
as something that’s foreign.

5. Rh Incompatibility
This means that if blood cells from baby cross mother bloodstream,
which can happen during pregnancy, labor, and delivery, mother
immune system will make antibodies against baby’s red blood cells.
Antibodies are parts of your body’s immune system. They destroy
foreign substances.

6. Rh Incompatibility
If mother have an Rh-negative blood type, considered sensitized to
her baby once her body has made these antibodies. This means that her
body might send these antibodies across the placenta to attack her
baby’s red blood cells.
In subsequent pregnancy maternal Rhesus antibodies cross the
placenta, resulting in haemolytic disease of the newborn.

8. Rhesus Incompatibility

9. Definition
•Rh incompatibility is a condition which develops
when there is a difference in Rh blood type between
that of the pregnant mother (Rh negative) and that of
the fetus (Rh positive).
•Usually placenta acts as barrier to fetal blood
entering maternal circulation. However, sometimes
during pregnancy or birth, fetomaternal hemorrhage
(FMH) can occur. The women’s immune system
reacts by producing anti-D antibodies that cause
sensitization.

12. Symptoms of Rh Incompatibility
•Unborn baby’s symptoms can range from mild to life-threatening.
When mother antibodies attack baby’s red blood cells, hemolytic
disease can occur. This means baby’s red blood cells are
destroyed.
•When baby’s healthy red blood cells are destroyed, bilirubin will
build up in their bloodstream.

13. Symptoms of Rh Incompatibility
•Bilirubin is a chemical that’s created from the
breakdown of red blood cells.
•yellowing of the skin and whites of the eyes,
which is called jaundice
•lethargy
•low muscle tone
•These symptoms will subside once treatment for
the Rh incompatibility is completed.

14. Risk for Rh Incompatibility
•Any woman who is Rh-negative and is having a child with a
father who is Rh-positive or with an unknown Rh status is at risk
for Rh incompatibility.
•If a mother became sensitized because of a miscarriage or
abortion, her first birth may be affected by Rh incompatibility.

15. Risk for Rh Incompatibility
•It takes time for the body to develop
antibodies, so first born children are usually
not affected.
•In subsequent pregnancy maternal Rhesus
antibodies cross the placenta, resulting in
haemolytic disease of the newborn.

16. Risk for Rh Incompatibility

17. Diagnosis of Rh Incompatibility
•There are no any physical symptoms can be seen in Rh-
incompatibility.
•If the women found out she is pregnant, she should undergo blood-type
test. This test determines her blood type and Rh factor.
•A blood test to determine Rh status will likely be done at first prenatal
visit.
•A positive indirect Coombs test is a sign of Rh incompatibility.

18. Diagnosis of Rh Incompatibility
•Higher-than-normal levels of bilirubin in infant’s blood is a sign of Rh
incompatibility. In a full-term baby who is less than 24 hours old, the
levels of bilirubin should be less than 6.0 milligrams per deciliter.
•Signs of red blood cell destruction in infant’s blood are signs of Rh
incompatibility.

19. Antenatal investigation protocol of Rh-negative
mothers
•Investigation of blood for Rh and ABO grouping become almost a
routine during the first antenatal visit in first trimester.
•If the women is found Rh-negative, Rh grouping of the husband is to
be done to find out whether the pregnancy is a result of incompatible
or compatible mating.
•If the husband found to be Rh-positive, further investigation are to be
carried out:

20. Obstetric history:
•If women is a primigravida with no previous history of
blood transfusion, it is quite unlikely that the baby will
be affected.
•In a parous women, a detailed obstetric history has to
be taken.
•History of prophylaxis administration of anti-D
immunoglobulin following abortion or delivery should
be enquired.

21. Antibody detection:
•In all cases of Rh-negative women irrespective of
blood grouping and parity, IgG antibody is detected by
indirect Coombs test.
•If the test is found negative at 12th week, it is to be
repeated at 28th and 36th week in primigravida. In
multigravida, the test is to be repeated at monthly
intervals from 24 weeks onwards.
•If the test is found positive: The patient should be
supervised in centers equipped to tackle with Rh
problem

22. Prevention of Rh-immunization
Antenatal period:
-Antenatal prophylaxis with anti-D
immunoglobulin in non-sensitized Rh-negative
pregnant women at 28 and 34 weeks of
gestation.

24. Postpartum period:
•Anti D-immunoglobulin is administered
intramuscularly to the mother 300 μg following
delivery
•All Rh-negative unsensitized women should receive
50 μg of Rh-immune globulin IM within 72 hours of
induced or spontaneous abortion, ectopic pregnancy.

25. Plan of delivery
•Unimmunized mothers: in cases where there is no detectable
antibody found during pregnancy, an expectant attitude is
followed till term. Tendency of pregnancy to overrun the expected
date should not be allowed.

26. •Immunized mothers: whenever there is evidence
of fetal hemolysis process in the fetus in utero, the
patient should be shifted to an equipped center
specialized to deal with Rh problems.
•An intensive neonatal care unit, arrangements for
exchange transfusion and an expert neonatologist
are the basic requirement to tackle the affected
babies.

27. Treatment of Rh Incompatibility for baby
Exchange transfusion in the newborn
• it is life saving procedure in severely affected hemolytic
disease of the newborn.
•The replacement temporarily helps to tide over the crisis
from anemia and hyperbilirubinemia for about two weeks.
Thereafter, the baby is quite capable to get rid of the
maternal antibodies by producing sufficiently his own Rh-
positive blood.

28. Phototherapy: phototherapy is to be continued
for 24hours.
•Phototherapy (blue or blue green light of 420-
470nm wave length) degrades bilirubin by photo-
oxidation and structured isomerization.
•Bilirubin is converted to less toxic polar isomer.
•These products are water soluble and therefore
readily excreted in the bile and urine.