I certainly don't consider myself a knowledgable person, but I have done a fair bit of travelling across time zones on the pill and other medication to be taken at regular intervals. What I do is to immediately adjust to the new time zone and take my medication at my normal time according to the new time zone. Travelling between American and Europe that means I am 6 or 7 hours off schedule. In most cases it says on the packet that if you miss one day it's not a problem, just start up the next day as if nothing happened. So I have never had my hormones go out of whack for that reason.