Low level of progesterone and estrogen in blood stimulate

Options

A. FSH-RH production
B. LH production
C. GH production
D. all of these

Explanation

To answer the question "Low level of progesterone and estrogen in blood stimulate," we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Hormones**: Recognize that progesterone and estrogen are female sex hormones that play crucial roles in the menstrual cycle and reproductive system.

2. **Understand Feedback Mechanism**: Understand that hormone levels in the body are regulated by a feedback mechanism. When hormone levels drop, the body responds to restore balance.

3. **Low Hormone Levels**: When the levels of progesterone and estrogen are low in the blood, this signals the body that there is a need for more of these hormones.

4. **Hypothalamus Response**: The low levels of progesterone and estrogen stimulate the hypothalamus, a region of the brain that controls the release of hormones.

5. **Release of FSH-RH**: In response to the low levels of these hormones, the hypothalamus secretes Gonadotropin-Releasing Hormone (GnRH), which is also referred to as Follicle Stimulating Hormone-Releasing Hormone (FSH-RH).

6. **Anterior Pituitary Gland**: The GnRH travels to the anterior pituitary gland, where it stimulates the secretion of Follicle Stimulating Hormone (FSH).

7. **Increased Estrogen and Progesterone Production**: The increase in FSH levels promotes the growth of ovarian follicles, which leads to an increase in the production of estrogen and progesterone from the ovaries.

8. **Conclusion**: Therefore, the correct answer to the question is that low levels of progesterone and estrogen stimulate the hypothalamus to release FSH-RH, which in turn increases the secretion of FSH and subsequently raises the levels of estrogen and progesterone.

### Final Answer:
Low levels of progesterone and estrogen in the blood stimulate the hypothalamus to secrete FSH-RH, leading to increased production of FSH from the anterior pituitary and subsequently increased secretion of estrogen and progesterone from the ovaries.

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