Which of the following causative agents of STDs can cross the placenta ?

Options

A. Hepatitis-B
B. HIV
C. Syphilis
D. All of these

Answer

To determine which causative agents of STDs can cross the placenta, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Causative Agents**: The question mentions three potential causative agents of STDs:
- Hepatitis B
- HIV (Human Immunodeficiency Virus)
- Syphilis

2. **Understand the Mechanism of Infection**:
- All three agents are known to be transmitted from an infected mother to her fetus. The placenta serves as a connection between the mother and fetus, and certain pathogens can cross this barrier.

3. **Evaluate Each Agent**:
- **Hepatitis B**: Although it is generally difficult for Hepatitis B to cross the placenta due to its size, it can cross under certain conditions, such as placental abruption.
- **HIV**: This virus is known to easily cross the placenta and can infect the fetus during pregnancy.
- **Syphilis**: The bacterium that causes syphilis can also cross the placenta and infect the fetus.

4. **Conclusion**: Since all three agents (Hepatitis B, HIV, and Syphilis) can potentially cross the placenta and transmit infections to the fetus, the correct answer is:
- **All of these**.

### Final Answer:
All of these (Hepatitis B, HIV, and Syphilis) can cross the placenta.

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