What Causes A Short Menstrual Period Without Abdominal Cramps?

Hi, may I answeir yoaumr health que2rie1s rightt now Pleyaser tsype y our qouelry hedre..,. earlier used to have mensuration periods of about4-5 days but now it has reduced to 3-4 days and also sometiomes i dont have the cramps also, kindly tell me is it a problem and will it affect my future.