I got spanked last night. It started out as role affirmation (which had been put off since Monday for various reasons), but turned to punishment after I confessed to a slip. While we were still in the role affirmation part, I asked Steve if he was spanking harder than usual because it seemed like it hurt more. He said no and I said well my pain threshold must be lower.
This morning I was trying to pinpoint why it hurt more last night and an idea occurred to me. Could it be because a certain aunt we all know and hate is visiting this week?
I decided to do some digging. My first step was to check my fertility charting software to find out exactly when previous cycles occurred (mine are irregular so I rely on charting to keep track) so I could see if they lined up with more painful spankings. Unfortunately, the cycles I have had since beginning DD lined up with spanking-free weeks so it was back to the drawing board.
Next I put my medical background to work by researching pain threshold and the female cycle in medical journals. I found something interesting. Research has found a link between estrogen and pain tolerance.
Researchers looked at why this occurs. When the body senses pain, opioids called endorphins and enkaphalins are released. These bind to receptors called to mu-opioid receptors, which are found throughout the brain. This results in the person's perception of pain being altered, making them more able to tolerate it.
When estrogen levels are decreased such as they are at the beginning and end of a menstrual cycle, fewer opioids are released and fewer receptors are activated. This has the effect of lowering the pain threshold, which is why spankings that occur during these times seem to hurt more than ones carried out in the middle of the cycle when estrogen levels are at their peak.