Which one of the following hormones is responsible for uterine contraction during parturition?

Options

A. Relaxin
B. Vasopressin
C. Oxytocin
D. Prolactin.

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks which hormone is responsible for uterine contractions during parturition (the process of giving birth).

2. **Identifying the Options**: The options provided are:
- a. Relaxin
- b. Vasopressin
- c. Oxytocin
- d. Prolactin

3. **Analyzing Each Hormone**:
- **Relaxin**: This hormone is primarily involved in relaxing the pelvic ligaments and cervix during childbirth, but it does not directly cause uterine contractions.
- **Vasopressin**: Also known as antidiuretic hormone (ADH), it regulates water balance in the body and does not play a significant role in uterine contractions.
- **Oxytocin**: This hormone is crucial for stimulating uterine contractions during labor. It is released in response to the stretching of the cervix and uterus, promoting strong contractions that help in the delivery process.
- **Prolactin**: This hormone is mainly responsible for milk production in the mammary glands and does not influence uterine contractions.

4. **Conclusion**: After analyzing the roles of each hormone, it is clear that oxytocin is the hormone responsible for uterine contractions during parturition.

5. **Final Answer**: The correct answer is option **c. Oxytocin**.

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