If the mother is Rh-ve and the father is Rh+ve, the condition of erythroblastosis foetalis may occur. This condition may be avoided by administrating anti - Rh antibodies to

Options

A. foetus, just after the birth.
B. mother, just after the birth.
C. mother, just before the birth.
D. both foetus and mother, just after the birth.

Answer

To solve the question regarding the prevention of erythroblastosis fetalis in the case of an Rh-negative mother and an Rh-positive father, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Erythroblastosis Fetalis**:
- Erythroblastosis fetalis is a condition that occurs when an Rh-negative mother carries an Rh-positive fetus. The mother’s immune system may recognize the Rh-positive blood cells of the fetus as foreign and produce antibodies against them.

2. **Role of Rh Factor**:
- The Rh factor is a protein that can be present on the surface of red blood cells. If a person has this protein, they are Rh-positive; if they do not, they are Rh-negative.

3. **Immune Response**:
- During the first pregnancy, if the fetus is Rh-positive, the mother’s immune system may not react strongly. However, during delivery, some of the fetal blood can enter the mother’s circulation, leading her immune system to produce anti-Rh antibodies.

4. **Subsequent Pregnancies**:
- If the mother becomes pregnant again with another Rh-positive baby, the previously formed antibodies can cross the placenta and attack the fetal red blood cells, leading to severe anemia and other complications in the fetus.

5. **Preventive Measure**:
- To prevent the formation of these antibodies, it is crucial to administer anti-Rh antibodies (Rh immunoglobulin) to the mother. This is typically done after the birth of an Rh-positive baby.

6. **Timing of Administration**:
- The anti-Rh antibodies should be administered to the mother just after the birth of the Rh-positive baby. This helps to neutralize any Rh-positive blood cells that may have entered the mother’s bloodstream during delivery, preventing her immune system from producing antibodies against Rh factor.

7. **Conclusion**:
- Therefore, the correct answer to the question is that anti-Rh antibodies should be administered to the mother just after the birth.

### Final Answer:
The condition of erythroblastosis fetalis may be avoided by administering anti-Rh antibodies to the mother just after the birth.

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