That’s a great question! Most of the time, your period will be about the same number of days each time regardless of how heavy or light it is. What determines how heavy or light your period is, is the thickness of the lining of your uterus that month. If anything, a lighter period may be a shorter period since the lining is more likely thinner. Plan for it to last the usual amount of time but remember periods sometimes have minds of their own, and may last a day longer or shorter for no clear reason, so be prepared!
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