Menstrual cramp is a common problem that occurs during the beginning of menstrual period. What could be the reason for this?

Explanation

**Step-by-Step Solution:**

1. **Understanding Menstruation**: Menstruation is a biological process that occurs in women, typically lasting from day 1 to day 5 of the menstrual cycle. It involves the shedding of the uterine lining.

2. **Phases of Menstrual Cycle**: The menstrual cycle consists of several phases, with the menstrual phase being the first phase where the endometrium (the inner lining of the uterus) breaks down and is expelled from the body.

3. **Role of Prostaglandins**: During the menstrual phase, a hormone called prostaglandin is released in large amounts. Prostaglandins are responsible for causing contractions in the uterus.

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