Drugs causing embryo malformations during pregnancy are called

Options

A. nicotine
B. sedatives
C. teratogens
D. tranquillizer

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks about drugs that cause malformations in embryos during pregnancy. It is essential to identify the specific term used for such drugs.

2. **Identifying Key Concepts**: During pregnancy, a mother is advised to avoid most medications because certain drugs can cross the placental barrier and affect the developing fetus.

3. **Role of the Placenta**: The placenta is a crucial structure that connects the mother to the fetus, allowing for nutrient and gas exchange while also acting as a barrier to protect the fetus from harmful substances.

4. **Effects of Certain Drugs**: Some drugs have the ability to cross the placental barrier and can induce abnormalities in the developing fetus. These abnormalities are referred to as fetal malformations.

5. **Defining Teratogenicity**: The ability of a drug to cause fetal abnormalities is known as teratogenicity.

6. **Identifying Teratogens**: Drugs that have the capacity to induce fetal malformations are specifically called teratogens.

7. **Conclusion**: Therefore, the correct answer to the question is that drugs causing embryo malformations during pregnancy are called **teratogens**.

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