The EXACT thing has happened to me, as well, OP.

I despise Facebook, but I have to use it, unfortunately. (Long story. ;) ) Anyways...Last month, I was speaking to a family member, in my private residence, about a very specific surgical procedure that interested me. I had not searched for it on my computer, nor had I ever posted anything at all (on Facebook or anywhere else, online) that might indicate such an interest. However, when I checked my Facebook account, a little later that day, there were 2 ads for clinics on the side of the page -- ads for that same, very specific procedure that I had only spoken of.

This has happened to me at least one time (that I was aware of) since then, too.

Thank you SO much for this thread, OP. I've always known about the privacy dangers related to FB, but I was seriously beginning to think that I was just imagining things or being too paranoid...