Very interesting question .......... it has got me thinking.

We started TTC in January this year and in February I had to fly from Brisbane-London-Vienna and then return (I was staying in London for 4 days on my way home). As this was a work related flight, it had been organised a few months ahead (i.e. before TTC) so wasnt able to cancel.

By the time I got to London on my flight home I realised AF was a few days late (very unusual for me) and got quite excited as I thought I may be pregnant however started bleeding a few days later as I was leaving London airport which I remember being unusually heavy and quite painful (just what you want to happen as you are about to board a 16 hour flight).

I never really thought about it .......... I just thought with all the time differences, sleep interruptions etc, it must have played havoc with my cycle.