Which complex of hormones induces lactation?

Options

A. Estrogen, Progesterone and hPL
B. Relaxin, estrogen and hCG
C. hCG and hPL
D. Oxytocin and prolactin

Answer

To answer the question "Which complex of hormones induces lactation?", we can break down the information step by step:

### Step-by-Step Solution:

1. **Understanding Lactation**: Lactation refers to the process of milk production and release from the mammary glands, which occurs after childbirth (parturition).

2. **Identifying Key Hormones**: The primary hormones involved in lactation are:
- **Prolactin**: This hormone is crucial for milk production. It is released by the anterior pituitary gland and is stimulated by the placenta after childbirth.
- **Oxytocin**: This hormone is responsible for the ejection of milk from the mammary glands. It is released during breastfeeding and helps in the contraction of the myoepithelial cells around the mammary glands.

3. **Evaluating Other Hormones**:
- **Estrogen and Progesterone**: These hormones are important for preparing the body for pregnancy and regulating the menstrual cycle but do not directly induce lactation.
- **Human Placental Lactogen (HPL)**: While HPL (also known as Human Chorionic Lactogen) plays a role in preparing the mammary glands for lactation, it is not the primary hormone responsible for milk production.
- **Relaxin**: This hormone helps in relaxing the smooth muscles but is not directly involved in lactation.
- **Human Chorionic Gonadotropin (HCG)**: This hormone is involved in maintaining pregnancy but does not have a role in lactation.

4. **Conclusion**: The hormones that specifically induce lactation are **Prolactin** and **Oxytocin**. Therefore, the correct answer to the question is the complex of hormones that includes Prolactin and Oxytocin.

### Final Answer:
The complex of hormones that induces lactation is **Prolactin and Oxytocin**.

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