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

Options

A. Relaxin
B. Lactogen
C. Gonadotropin
D. Oxytocin

Answer

To determine which hormone is not secreted by the human placenta, we need to analyze the hormones typically produced by the placenta and identify the one that does not belong to this group.

### Step-by-Step Solution:

1. **Understand the Role of the Placenta**:
- The placenta is a vital organ that develops in the uterus during pregnancy. It facilitates nutrient and waste exchange between the mother and the fetus and also produces several hormones essential for maintaining pregnancy.

2. **Identify Hormones Secreted by the Placenta**:
- The placenta secretes several important hormones, including:
- **Relaxin**: Helps in the relaxation of the pubic symphysis during childbirth.
- **Human Placental Lactogen (hPL)**: Reduces glucose consumption in the mother to ensure more glucose is available for the fetus.
- **Human Chorionic Gonadotropin (hCG)**: Inhibits the release of follicle-stimulating hormone (FSH) and luteinizing hormone (LH), which are important for maintaining pregnancy.

3. **Identify the Hormone Not Secreted by the Placenta**:
- **Oxytocin**: This hormone is produced by the hypothalamus and stored in the pituitary gland. It plays a role in uterine contractions during labor and milk ejection during breastfeeding but is not secreted by the placenta.

4. **Conclusion**:
- Based on the information gathered, the hormone that is not secreted by the human placenta is **Oxytocin**.

### Final Answer:
The hormone that is not secreted by the human placenta is **Oxytocin**.

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