do all pregnant women require doctor’s approval to fly?
I realize the rules may be different depending on the airline, so I’m limiting my query to airlines that fly from Taiwan to the U.S.
The lady in question is only a couple of month pregnant.
THANKS for your help!
first trimester: no worries, don’t even notify anyone.
second trimester: fly unless you have a known problem, eg preeclampsia, high blood pressure, illness.
third trimester: not recommended unless you’re checked OK by an obstetrician, and not at all in the last month.
these are general rules-of-thumb, and individual airlines may beg to differ. also check your medical insurance covers you.
No. But if she’s pregnant, I hope she has seen a doctor. Most pregnancies, are easy and all that, yet as a woman, I think a first time pregnant girl should atleast see a doc. before being whisked away to another country. 
From experience, if you have heavy bags you may need to lift and the doctor for whatever reason has told you to not lift things like this, you should inform the airline so they can arrange assistance. I got caught in an airport and nobody could help me lift the suitcase into the x-ray machine, as the person operating the machine was not allowed to touch the bags, and nobody else was available to help.
As long as Mommy is in good health, there is no need to worry of traveling. some people are superstitious about pregnancy thou.