What is menstruation?

Explanation

**Step-by-Step Text Solution:**

1. **Definition of Menstruation**: Menstruation refers to the monthly shedding of the uterine lining in females.

2. **Uterus and Endometrium**: The uterus, also known as the womb, is a vital organ in the female reproductive system. The inner lining of the uterus is called the endometrial layer, which plays a crucial role in the menstrual cycle.

3. **Process of Shedding**: Every month, if fertilization does not occur, the endometrial layer is shed off. This process is what we refer to as menstruation.

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