When a woman is on the birth control
pill there is an easy way she can delay
the onset of menses. This is done by continuing to take the active pills (i.e., skipping the placebo pills and starting a new pack of active pills without missing any days) in a new pack. We consider this the continuous use of oral contraceptive pills, which has the benefit of deferring a monthly menses.
Nevertheless, this will sometimes result in breakthrough bleeding.