Ya i am 28 years old.i am in post ovulation stage..my periods are due on 5th dec but i want to prepone it by 2-3 days.how to do it?

Oral contraceptive: may be beneficial, though there is no guarantee that your innate hormonal cycle will obey the pill. And I do not really recommend for you to alter your period as consequences to doing so may be more troublesome that it is worth. You may miss your period entirely then bleed heavily later and for longer time. Or you may ovulate sooner than you expect and conceive.