There is an other factor here you need to be aware of...Estrogen Vs Progestin
There are many different types of BC and the "Pill" and they dont all work the same nor are made from the same thing.
The ones made with 20-50mgs of Estrogen are the ones that carry a greater risk of blood clots and heart problems in GENERAL...smoking just adds more risk to it.
Where Progestin made BC's Do not increase the risks smoking or not.
There was a swing over b/c of the risks associated. 70-80's basically all BC's where all or mostly Estrogen....Today most BC's are made of all or mostly Progestin. But it doesnt hurt to check, be more then happy to pull the info for specific pills if you have trouble finding what exactly is in yours.
This is also why the studies numbers are so wacky if you compare them but are unaware of the change over.
I'll pull the studies if anyone is interested.