That would sure be nice! I am miserable!
I actually was researching signs that labor is near earlier today and a few of the pages i found said weight loss is a sign :)
The same exact thing happened to me. I went in and I was 190, then exactly one week later I went in and was 183. Same thing with me, the doctor wasn't worried at all.
I haven't been on any special diet and she said my weight gain was fine last week. I am due in 6 days and it hasn't caused me any problems.
It is normal, it is actually preferred for women who are overweight to go on some type of diet, or lose weight since it can cause pregancy problems or delivery trouble, i hear the doctor i work with tell his patients this all the time.