I just moved from Hong Kong back to the UK. My personal experience is. Take antacids with you on the plane. Purchase a good pair of pressure socks, your feet will swell and this will reduce the swelling. As it's a long flight every hour try to walk around for 3-4 minutes as this will help circulate the blood in your legs and help with swelling. Drink lots of water. I took and empty bottle with me through security and then filled it up and the air hostess filled it up for me - you'll get incredibly thirsty.
I spoke to my obgyn before I left and this is what he told me. Just try to relax and sleep as much as possible.
Stay hydrated and get up once an hour to stretch so you don't get blood clots. I flew across the US when I was 33 weeks and it wasn't to bad. Just be sure to bring snacks and drink lots of water.
Well yeah. I'm asking for advise on air travel while being that pregnant...
Talk to your doctor about it