Within the States, it is relatively simple to figure things out with airlines. You simply go online and read, and you will know policies about liquids, carry-ons, luggage allowance, etc. Not so outside of the United States. Airlines, regions, and even individuals within a single airport vary in their preferences. One would think you could just read or call to get information, but after travelling in the last couple of months with a toddler, and infant (not mine), and a large pregnant belly, I am here to tell you that it just helps to expect for incredible inconvenience no matter what. If you have done much international travelling, you probably knew all of this already.
Last summer we went to Germany when I was 7 months pregnant, and no one even seemed to notice. This trip, I didn't even think about getting a doctor's note to travel because I had no use for it last summer. Big mistake. It wasn't a big deal on the way; I got some raised eyebrows and had to sign a liability form for one flight. I also had to put a pillow between my stomach and the seatbelt. I think it was supposed to protect the baby in case a suitcase flew out and hit me in the stomach... maybe they know something that I don't.
On the way back, however, I was escorted by a woman to visit the airport "hospital" where they expected me to pay for an examination that I knew I didn't need! They told me it was for my own security, and I assured them that I had seen my doctor the week before I travelled, and I felt very secure. Ultimately, I submitted to the examination, but I did not pay for it... the doctor determined that my temperature was normal, my blood pressure was normal, and I had a baby moving around in my stomach. Thanks for the helpful information!