The first time i see my period it last for 7days and now it reduces to 3days what causese this?

Answers:

It's a short time ago normalize. When you first start period are unexpected. Eventually the regulate. A common length can second from 3-7 days, so be content that you find short ones.

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Hi, powerfully, if you embezzle Birth Control, that can wreak your length to make over.
Hope this help.

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The establishment of your menstrual cycle is a big event for your body. It can lug a while for it to settle into its inborn rhythm. There is nil unusual around your experience.