Hi Welcome to HCM progestogen hormone in tablet form, which is taken three times a day for three days before your period is due and then for duration of your holiday to delay the period. At the end of this time, the tablets are stopped and your period starts as normal. It is available on prescription from your GP. You should take the tab 2-3 days before your period not before travelling. As soon as you stop it you will have periods within 2 to 3 days after stopping. So if you want to delay it you should carry that many pills. Hope i have provided the information you needed. Have nice journey.