Which of the following hormones is not a secretory product of human placenta?

Options

A. Prolactin
B. Estrogen
C. Progesterone
D. Human chorionic gonadotropin

Answer

To solve the question "Which of the following hormones is not a secretory product of human placenta?", we will analyze the options provided and identify which hormone is not produced by the placenta.

### Step-by-Step Solution:

1. **Identify the Hormones**: The options given are:
- Prolactin
- Estrogen
- Progesterone
- Human Chorionic Gonadotropin (HCG)

2. **Understand Placental Hormones**: The human placenta acts as an endocrine gland during pregnancy and secretes several hormones. The main hormones produced by the placenta include:
- Estrogen
- Progesterone
- Human Chorionic Gonadotropin (HCG)
- Human Placental Lactogen (HPL)

3. **Analyze Each Option**:
- **Estrogen**: Secreted by the placenta, it plays a crucial role in maintaining pregnancy.
- **Progesterone**: Also secreted by the placenta, it helps in preparing the uterus for pregnancy and maintaining it.
- **Human Chorionic Gonadotropin (HCG)**: This hormone is secreted in large amounts during early pregnancy and is essential for maintaining the corpus luteum.
- **Prolactin**: This hormone is not secreted by the placenta; it is produced by the anterior pituitary gland and is primarily involved in milk production after childbirth.

4. **Conclusion**: Based on the analysis, the hormone that is not a secretory product of the human placenta is **Prolactin**.

### Final Answer:
**Prolactin** is not a secretory product of the human placenta.

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