Which hormone stimulates the secretion of milk during sucking of milk by baby
Or
Which hormone is responsible for milk ejection after an birth of the baby

Options

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

Answer

### Step-by-Step Solution:

1. **Understanding the Question**: The question asks about the hormone responsible for stimulating milk secretion during breastfeeding and the hormone responsible for milk ejection after the birth of a baby.

2. **Identifying the Process**: When a baby suckles at the breast, it stimulates the nerve endings in the mother's nipple. This stimulation is crucial for the release of certain hormones.

3. **Role of Nerve Endings**: The sucking action of the baby activates the nerve endings in the nipple, which sends signals to the mother's brain.

4. **Hormonal Response**: The brain responds to these signals by instructing the pituitary gland to release oxytocin.

5. **Function of Oxytocin**: Oxytocin is known as the "milk ejection hormone." It causes the mammary glands to contract and release milk, allowing the baby to feed.

6. **Letdown Reflex**: This entire process of milk ejection triggered by the baby’s suckling is known as the "letdown reflex."

7. **Conclusion**: Therefore, the hormone responsible for stimulating milk ejection during breastfeeding is **oxytocin**.

### Final Answer:
The hormone responsible for milk ejection after the birth of the baby is **oxytocin**.

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