Which of the following condition arises in subsequent pregnancies after the first normal pregnancy ?

Options

A. Rh incompatibility disease
B. Erythroblastosis foetalis
C. Muscular dystrophy
D. Both (A) and (B)

Answer

To solve the question "Which of the following conditions arises in subsequent pregnancies after the first normal pregnancy?", we will analyze the options provided and understand the underlying biological concepts.

### Step-by-Step Solution:

1. **Understanding Rh Factor**:
- The Rh factor is a protein that can be present on the surface of red blood cells. If it is present, the blood type is Rh positive (e.g., O positive); if it is absent, the blood type is Rh negative (e.g., O negative).

2. **First Pregnancy Scenario**:
- If a mother is Rh negative and the father is Rh positive, their first child may inherit the Rh positive trait from the father. During delivery, there is a possibility that the fetal blood may mix with the mother's blood, exposing the mother to Rh positive antigens.

3. **Formation of Antibodies**:
- Upon exposure to Rh positive blood, the mother's immune system may produce antibodies against the Rh factor. This process is known as sensitization.

4. **Subsequent Pregnancies**:
- In any subsequent pregnancies, if the mother is Rh negative and the next child is again Rh positive, the antibodies formed during the first pregnancy will attack the fetal red blood cells, leading to a condition known as hemolytic disease of the newborn (HDN).

5. **Erythroblastosis Fetalis**:
- This condition is a severe form of HDN where the mother's antibodies destroy the fetal red blood cells, leading to anemia and potentially fatal outcomes for the fetus.

6. **Identifying the Correct Answer**:
- Given the options:
a. Rh incompatibility disease
b. Erythroblastosis fetalis
c. Muscular dystrophy
d. Both a and b
- The correct answer is **d. Both a and b**, as both conditions can arise in subsequent pregnancies after the first normal pregnancy if the mother is Rh negative and the child is Rh positive.

### Final Answer:
**d. Both a and b**