I need the real 4-1-1 on you guessed it: CIGARS! Does an occasional cigar (1 per week) cause hair loss?

Occasional cigars or cigarettes do not cause hair loss. If you are concerned it is best to consult with your doctor.  Smoking in general is not good for you and is not good for wound healing.

Nicotine in any form causes the small blood vessels in the skin to contract shrink and shrink down.  This can impede healing and take of grafts.  Smoking can also cause a myriad of other problems that have been well publicized.  That said, a cigar once a week should have little adverse effect on your hair transplant.  Ideally you abstain for two weeks before and after surgery.

I don't think so that one cigar a week will produce you hair loss. But it is very well documented about impaired microcirculation (scalp or other body areas) of those moderate and heavy daily smokers that have plastic or hair restoration surgery. Obviously smoking can cause cancer.

Although writing cigars and hair transplant in the same sentence seems extremely unorthodox, you are probably just fine enjoying your occasional cigar with NO worries. 

Although not recommended, the occasional cigar will not cause any long term effects with your hair transplant. 

There are more than 7,000 chemicals in smoke, cigarette or otherwise. Smokers are prone to cancer of many types because of the damaging effects of oxidizers contained in smoke that lead to DNA damage. Smokers have a life expectancy of 11 years less than non smokers. Smokers tend to have thinner donor material than non-smokers. It is up to you whether you smoke or not. Smoking will also harm your sexual performance.

You can smoke cigars any time after the first day of a hair transplant probably with little effect from the smoke