First off, I know that any smoke while you are PG (or anytime) is bad. That being said, I am really stressing myself about not being around family members my whole pregnancy because they all smoke. My sister is taking me to Red Lobster tomorrow for my birthday and will smoke in the car with me. I do roll my window down all the way, but how bad is being around that smoke (one cigg on the way there and one on the way back probably)? This REALLY stresses me out because I dont wanna be around it cause I think I'm hurting the baby, but at the same time I have isolated myself so much this pregnancy by not going to family member's homes because they all smoke. I have asked her not to smoke around me before but she still does it, and I don't wanna keep bringing it up because she is paying for my meal. The only other option is to not go at all. I ride with my sister about once a month to give an example of how often I'm around it.
Occasional second hand smoke while pregnant?
With my first pregnancy we lived in a 2 bedroom apartment with my brother who was a chain smoker. He never smoked in the shared living areas, but he still smoked in his room, constantly, and we could smell it in the hallway that the two bedrooms shared. It definitely stressed me out a bit, but I tried not to worry too much about it because I figured the stress would probably be more harmful to the baby than the minimal amount of smoke exposure.
If I were you, I would just make sure that you sit next to a window and keep it well cracked while she is smoking. I'm assuming that the restaurant is smoke free--aren't they all by now? If the car ride is the only exposure that you will have, and it will only be long enough for one cigarette each way, then I would just do my best to keep it aired out and not worry about it too much. I know that no amount of smoke exposure is really a good thing, but I highly doubt that such a small exposure, even once a month, would cause any lasting harm to your baby.
Good luck, and enjoy the cheddar bay biscuits! Now I'm craving seafood!