How much can smoking affect your chances of conceiving?

I do smoke. Not a lot just the odd few a day. I plan on not smoking if I got my bfp and I'm sure I'll be fine in quitting as I would not smoke during pregnancy or after (just my opinion) I was just wondering how much me smoking is affecting my chances of conceiving quicker? What is the likelihood I'll conceive if I stop before my bfp? Please help ladies and thanks in advance