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 answer the question "Which of the following causative agents of STDs can cross the placenta?" we will analyze each option provided: Hepatitis B, HIV, and Syphilis.

### Step-by-Step Solution:

1. **Understanding the Causative Agents**:
- We need to identify the three causative agents mentioned: Hepatitis B, HIV, and Syphilis.

2. **HIV (Human Immunodeficiency Virus)**:
- Research shows that HIV can cross the placenta during pregnancy. This means that if a mother is infected with HIV, the virus can be transmitted to the fetus through the placenta.

3. **Syphilis**:
- Syphilis is another STD that can cross the placenta. It can infect the fetus as early as 14 weeks of gestation, and the risk of fetal infection increases as the pregnancy progresses.

4. **Hepatitis B**:
- Hepatitis B does not typically cross the placenta during pregnancy. However, it can be transmitted to the baby during delivery (vaginal or cesarean). The transmission occurs through contact with the mother’s blood or bodily fluids during the birthing process.

5. **Conclusion**:
- Since both HIV and Syphilis can cross the placenta and infect the fetus, and while Hepatitis B does not cross the placenta but can still infect the baby at birth, the correct answer to the question is that all three can be associated with transmission to the fetus in some way.

### Final Answer:
All of these (HIV, Syphilis, and Hepatitis B) can be associated with transmission to the fetus, but specifically, HIV and Syphilis can cross the placenta.