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Because the level of prostaglandins (the pain chemical) is at absolute highest on the first day of your period. High levels of prostaglandins lead to more strong, more frequent, and more painful contractions right on the first day.
Here’s a step-by-step understanding on why the first day of period pain hurt so bad.
1. The Prostaglandin Peak
Just before your period starts, the lining of your uterus produces a high volume of prostaglandins (the pain chemical). These levels are at their absolute highest. often causing bad period pains on first day.
- What they do: They tell your uterine muscles to contract (squeeze) to help shed the lining.
- The Result: High levels lead to stronger, more frequent, and more painful contractions right at the start.
2. The Oxygen Squeeze
On the first day, the uterus is working its hardest to begin the flow. When the uterine muscles contract forcefully due to prostaglandins, they can squeeze the nearby blood vessels shut.
- What happens: This temporarily cuts off the supply of oxygen to the muscle tissue of the uterus.
- The Result: When a muscle is deprived of oxygen, it sends out intense pain signals. This is why the cramps feel like a sharp throbbing sensation.
3. Narrow Opening Of The Cervix
The cervix is the narrow opening at the bottom of the uterus. It must slightly open to allow the period blood and tissue to pass.
- What happens: For many, especially younger women, this passage is very narrow. As the uterus pushes against this narrow opening on the first day, it can cause intense cramping.
4. Maximum Shedding On Day 1 And Day 2
The volume of tissue and blood being shed is often heaviest on the first and second day of your period. Hence the uterus must contract more strongly to move this volume of blood and tissue out, leading to severe period pain on first day. This leads to more noticeable and severe pain compared to the lighter pain during the end days of the period.
More Answer For You
- Do Prostaglandins Cause Hair Loss?
- What are The Types of Prostaglandins and Their Functions?
- Do Prostaglandins Cause High Blood Pressure?
- Can Prostaglandins Cause Anxiety?
- Do Prostaglandins Cause Inflammation?
- Do Prostaglandins Cause Fever?
- Do Prostaglandins Cause Heartburn During Periods?
- Do Prostaglandins Cause Heavy Periods?
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