Usually whatever insurance you had at the time your wife became pregnant is responsible if a new policy doesn't take over. I don't know how that works if you leave the country, though. The first thing you should do is ask your current insurer. Also, if you are being transferred, your employer should take care of it and make sure you are covered.

How pregnant will she be when you move? They won't let her fly after seven months. Flying actually can induce labor because of the decreased air pressure.