Female reproductive cycle is regulated by

Options

A. Estrogen
B. Progesterone
C. Relaxin
D. Both (1) & (2)

Answer

**Step-by-Step Solution:**

1. **Identify the Key Hormones**: The female reproductive cycle is regulated by several hormones. The primary hormones involved are Luteinizing Hormone (LH), Follicle Stimulating Hormone (FSH), Estrogen, and Progesterone.

2. **Understand the Functions of Each Hormone**:
- **Luteinizing Hormone (LH)**: This hormone plays a crucial role in triggering ovulation and the development of the corpus luteum.
- **Follicle Stimulating Hormone (FSH)**: FSH is responsible for stimulating the growth of ovarian follicles in the ovary before the release of an egg.
- **Estrogen**: This hormone is involved in the regulation of the menstrual cycle and is responsible for the development of female secondary sexual characteristics.
- **Progesterone**: This hormone prepares the endometrium for a potential pregnancy after ovulation and helps maintain pregnancy.

3. **Evaluate the Options**:
- The first option mentions estrogen, which is indeed a regulator of the female reproductive cycle.
- The second option mentions progesterone, which is also a regulator.
- The third option mentions relaxin, which is not involved in the regulation of the female reproductive cycle but is secreted during pregnancy.
- The fourth option states "both 1 and 2," which is correct as both estrogen and progesterone regulate the cycle.

4. **Conclusion**: The female reproductive cycle is regulated by estrogen and progesterone, making the correct answer "both 1 and 2."

**Final Answer**: The female reproductive cycle is regulated by estrogen and progesterone (both 1 and 2).

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