This is a confusing topic and I think whether lidocaine is used during pregnancy depends on the doctor.
A few years ago, I had to have dental work done when I was pregnant because there was an infection. The dentist used lidocaine at that time and never mentioned a thing.
I'm pregnant with my second child now and had a small accident recently and got a cut on my arm. The doctor didn't want to use lidocaine, so he applied a skin adhesive instead of stitching the cut.
Either new information has been revealed about lidocaine that doctors no longer want to use it or it just depends on the doctor.