Which of the following is not a placental hormone ?

Options

A. progesterone
B. estrogen
C. hCG
D. prolactin

Answer

To determine which of the following is not a placental hormone, we need to analyze each option provided: Progesterone, Estrogen, HCG, and Prolactin.

### Step-by-Step Solution:

1. **Understanding the Placenta**: The placenta is an essential organ that develops during pregnancy, serving as the interface between the developing embryo (or fetus) and the maternal body. It plays a crucial role in nutrient and gas exchange.

2. **Hormones Produced by the Placenta**:
- **Human Chorionic Gonadotropin (HCG)**: This hormone is produced by the placenta shortly after implantation and is crucial for maintaining pregnancy.
- **Estrogen**: The placenta produces estrogen, which is important for the regulation of various functions during pregnancy.
- **Progesterone**: This hormone is also produced by the placenta and is vital for maintaining the uterine lining and supporting pregnancy.

3. **Identifying Non-Placental Hormones**:
- **Prolactin**: This hormone is primarily produced by the pituitary gland and is involved in milk production and other reproductive functions. It is not produced by the placenta.

4. **Conclusion**: Among the options provided, Prolactin is the hormone that is not produced by the placenta. Therefore, the correct answer is **Prolactin**.

### Final Answer:
Prolactin is not a placental hormone.

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