Hookah during TWW?

So I'm not really a smoker but I used to smoke hookah now and then. for those who don't know its flavored tobacco but contains little to no nicotine and I think no tar at all. I haven't in awhile and I've been wanting to smoke one more time before I get pregnant. Been TTC for 7 months. AF is due August 17th. Thought about maybe smoking today and getting it out of my system but I'm wondering if it's too risky as far as effecting me becoming pregnant? With having no luck TTC so far I worry for everything so figured I'd get opinions?