First of all, congratulations!!
I bet you are excited and scared all at once!
I had a mc back in Feb at 9 weeks, and then conceived again before Christmas. I went skiing over Christmas, and I don't know about the altitude, but unfortunately this one also ended in mc at about 6 weeks. I have read somewhere that air travel very early in pg can be bad, but I've seen no proof of this. I think you can probably worry about everything after you've had a mc and really there is nothing we can do!
I think that you need to speak to your doctor as soon as possible and see if they will send you for a reassurance scan - they are unlikely to do anything before about 6 weeks, as it is unlikely to see the heart beat before then. Some ladies on here have found their doctors very understanding, while others have had to think about saying they've had some bleeding in order to get referred to the EPU. I have to say that I wouldn't want to tempt fate like that, but if my doctor won't give me an early scan when/if I get pg again, I think I'll see about paying for one privately.
Anyway, try and relax and not to worry, although I know how difficult that is!
There are lots of understanding ladies on the TTC after mc thread, many of whom have had more than 1 mc, so you'll find lots of support there. I think there is a pg after mc thread too, over on the pg treads, which you may find helpful - I've not actually been over there yet!
HTH - Take care of yourself
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