What Is PMS?

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PMS is the effect of the menstrual cycle when the progesterone at the, few days before onset of menses. The drop in the progesterone in the brain and metabolites and progesterone in the brain. Progesterone in the brain acts sort of like Valium in the brain it's very calming, it's actually used in anesthesia for putting you to sleep.

So it's a mellowing hormone if you will, but then when it drops so it's almost like the brain is in Valium withdrawals so it's a little bit of vulnerability, and that can be triggered. It usually doesn't have its onset until you've been menstruating for three or four years. So the average age of onset of menses in the United States and Caucasian girls is age 12.1.

So not until they're 15, 16 do they usually even notice any of what we typically call PMS.