i travelled a 13 hours flight when i was 19weeks and another 13 hours flight back home at 31weeks (with gynae safe to flight letter) .. it is best to seek your gynae advice because they know yours and baby's condition .. usually 1st trimester is the most crucial time, foetus is developing .. you really need to take care .. but again, i'd suggest you ask your gynae .. :)
I travelled to Japan when I was somewhere btw 11-13 weeks pregnant but there was pre-covid. Relatively safe though but I had mask worn throughout (that time got outbreak of measles but not serious). I even climbed mountain. I didn’t even consult gynae. But I was past first trimester alr. Maybe you want to play safe and travel after first tri?
I travelled around 6 weeks, doctor said it was ok. 4hrs flight it was . major issues were morning sickness and feeling dizzy other than that I was ok. now at 23 weeks. check with gynea just to not be worried alot. take care 😊
Talk to your gynae for advice as gynae is the one monitoring you and baby :)