For women losing weight...

Amanda • Expecting baby #2 Christmas Day. Our son is 3 and super excited to find out if he is having a baby brother or sister.
I am currently down 17lbs and am at 12w+6. If you lost a lot of weight during your pregnancy when did it turn around? When did you start gaining weight back? I am 5'9" and 166 lbs and am currently losing 1-2lbs per week. I have a little excess maybe 10lbs but beyond that I'm going to be too skinny for my liking.