At 45, postponing your period for a short trip is quite safe and commonly done. The usual medicine for this is norethisterone, started a few days before your period is due and continued through the trip. Your period usually starts within two to three days of stopping it.
Next Steps
See your gynaecologist about a week before your trip so they can prescribe the right course and check it suits your health history.
Health Tips
Don't start this on your own without your doctor's guidance, especially if you have any bleeding or clotting problems.