Hi Bratt
It's probably worth speaking to your clinic about this and solicit their opinion. Here's my experience though. I do sympathise with you.
I had stopped smoking well before our first cycle in 2003 using the NHS program and the lozenges. Then we got DH's dx and I went off the deep end a bit and started smoking again. I stopped again using the lozenges and took them the whole way through my treatment cycle including after ET though by that stage I was only using a couple of lozenges a day.
I did all this with my consultant's blessing. His personal opinion was that it wouldn't affect treatment and was better to use NRT than smoke. Anyway, got BFP and doesn't seem to have affected DS in anyway. Born on his due date weighing 8lb 3oz.
Also, fyi, the NHS view on NRT in pregnancy is the same. If a woman is having difficulty quitting then NRT is better than smoking as you are only receiving the nicotine and not all the toxins associated with inhaling the smoke.
Could you get yourself on one of the NHS Stop Smoking courses? They really are very good.
I'm sure you'll get mixed opinions on this question.
Good luck, I know how hard it is, Succotash