Which of the following structure release progesterone hormone during pregnancy ?

Options

A. Placenta
B. Ovary
C. Pituitary gland
D. Both (1) & (2)

Answer

To answer the question "Which of the following structures release progesterone hormone during pregnancy?", we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Hormone**: The hormone in question is progesterone. It plays a crucial role in maintaining pregnancy by preparing the uterus for implantation and supporting the early stages of pregnancy.

2. **Identify the Structures**: The options given are:
- A) Placenta
- B) Ovary
- C) Pituitary gland
- D) Both A and B (Placenta and Ovary)

3. **Function of the Structures**:
- **Ovary**: The ovaries produce progesterone, especially after ovulation. This hormone is essential for thickening the endometrium (the lining of the uterus) to support a potential pregnancy.
- **Placenta**: During pregnancy, the placenta takes over the production of progesterone after the first trimester, ensuring that the uterine environment remains suitable for the developing fetus.
- **Pituitary Gland**: The pituitary gland does not produce progesterone; it secretes other hormones such as LH (Luteinizing Hormone) and FSH (Follicle Stimulating Hormone) that regulate the reproductive system.

4. **Conclusion**: Since both the ovary and the placenta release progesterone during pregnancy, the correct answer is option D) Both A and B.

### Final Answer:
The structures that release progesterone hormone during pregnancy are both the **Placenta and Ovary** (Option D).

---