Changes in GnRH pulse frequency in females is controlled by circulating levels of

Options

A. oestrogen and inhibin
B. progesterone
C. progesterone and inhibin
D. oestrogen and progesterone

Answer

**Step-by-Step Solution:**

1. **Understanding GnRH**: GnRH stands for Gonadotropin-Releasing Hormone. It is a hormone produced in the hypothalamus that stimulates the release of gonadotropins (LH and FSH) from the anterior pituitary gland.

2. **Role of Gonadotropins**: Gonadotropins, which include Luteinizing Hormone (LH) and Follicle-Stimulating Hormone (FSH), are crucial for regulating the reproductive system. They stimulate the ovaries to produce estrogen and progesterone.

3. **Hormonal Feedback Mechanism**: The levels of GnRH are regulated by a feedback mechanism involving the sex hormones. In females, the primary sex hormones are estrogen and progesterone.

4. **Influence of Estrogen and Progesterone**: High levels of estrogen and progesterone can inhibit the release of GnRH through negative feedback, while low levels can stimulate its release. This creates a pulse frequency of GnRH that is responsive to the levels of these hormones.

5. **Conclusion**: Therefore, the changes in GnRH pulse frequency in females are controlled by the circulating levels of estrogen and progesterone.

**Final Answer**: The changes in GnRH pulse frequency in females are controlled by circulating levels of estrogen and progesterone.

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