Which of the following event after parturition ensure milk secretion :

Options

A. Increased estrogen
B. Increased oxytocin
C. Decreased oxytocin
D. Decreased estrogen and progesterone

Answer

To solve the question regarding which event after parturition ensures milk secretion, we can break down the information as follows:

### Step-by-Step Solution:

1. **Understanding Parturition**: Parturition is the process of giving birth. After this event, several hormonal changes occur in the body, particularly in relation to lactation (milk production and secretion).

2. **Identifying Key Hormones**:
- **Prolactin**: This hormone is primarily responsible for milk production (lactogenesis) in the mammary glands.
- **Oxytocin**: This hormone plays a crucial role in the actual secretion of milk (let-down reflex) from the mammary glands.

3. **Analyzing the Options**:
- **Increased Estrogen**: While estrogen levels do change during pregnancy and after parturition, they are not directly responsible for milk secretion.
- **Increased Oxytocin**: This hormone is released in response to suckling and helps in the ejection of milk from the mammary glands.
- **Decreased Oxytocin**: This would not promote milk secretion.
- **Decreased Estrogen and Progesterone**: While these hormones decrease after parturition, they do not directly ensure milk secretion.

4. **Conclusion**: The event that ensures milk secretion after parturition is the **increased oxytocin** levels, which facilitate the milk ejection reflex during breastfeeding.

### Final Answer:
The correct answer is **increased oxytocin**.

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