My sil went to Britain and France over christmas when she was 10-15 wks and was fine. That said, I'd side with the others who have posted and would urge you to consider ms and exhaustion. You might be just fine, you might be wretched, more likely you'll be somewhere between the two. I was adjusting to living in Oz, planning a wedding, juggling new rellies and ones from overseas in my first tri and it half killed me.