Which of the following hormones is not secreted by human placenta?

Options

A. hCG
B. Estrogens
C. Progesterone
D. LH

Explanation

To determine which hormone is not secreted by the human placenta, we will analyze the options provided and identify the hormones associated with the placenta.

### Step-by-Step Solution:

1. **Understand the Role of the Placenta**:
- The placenta is an organ that connects the developing fetus to the uterine wall, allowing for nutrient uptake, waste elimination, and gas exchange between the mother and the fetus. It also functions as an endocrine organ, producing several hormones.

2. **List the Hormones Secreted by the Placenta**:
- The placenta secretes several important hormones, including:
- **Human Chorionic Gonadotropin (HCG)**: Helps maintain the corpus luteum and supports pregnancy.
- **Estrogen**: Involved in regulating various functions during pregnancy.
- **Progesterone**: Maintains the uterine lining for a successful pregnancy.
- **Human Placental Lactogen (HPL)**: Plays a role in regulating maternal metabolism and fetal growth.

3. **Identify the Hormone Not Secreted by the Placenta**:
- The options given are:
- HCG (Human Chorionic Gonadotropin)
- Estrogen
- Progesterone
- **Luteinizing Hormone (LH)**

4. **Determine the Source of Each Hormone**:
- HCG, estrogen, progesterone, and HPL are all produced by the placenta.
- **Luteinizing Hormone (LH)** is produced by the anterior pituitary gland and is not secreted by the placenta.

5. **Conclusion**:
- Based on the analysis, the hormone that is not secreted by the human placenta is **Luteinizing Hormone (LH)**.

### Final Answer:
The hormone that is not secreted by the human placenta is **Luteinizing Hormone (LH)**.

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