There are several ways in which periods can be delayed. The first involves taking a drug called a progestogen.
This medication needs to be taken three times daily while the woman wants to postpone her period, and once the drug is stopped it usually takes two or three days for her period to begin again. This treatment is not 100 per cent effective. Some bleeding will sometimes occur while the drug is being taken, and side effects such as fluid retention, breast tenderness and mood disturbance can be a problem.
The second method involves taking the combined oral contraceptive pill. This needs to be started well before the woman needs to postpone her period, and to avoid having a period at an inconvenient time, two packs of pills can be taken consecutively without a break. Provided that the woman suffers no significant side effects, this method usually works well. It is obviously ideal if the woman needs contraception.
The doses of hormones in the pill are quite considerable, and if you do not need the pill for contraception I believe it would be better to avoid taking it.