I had a dentist appointment 2morrow for this. At my last appointment my dentist said it was a abscess, a infection he said alot of pregnant women get this.
I have one my left hand side. He scheduled me to come back 2morrow he said he would remove the source which is causing it. Which is a cavity that went to long with out being treated c auseing a infection. . Im so nervous my app is at 9 in the morning I hate the dentist.
But any infection untreated is bad for the baby... Ill post 2morrow to tell u what he did to remove it
My sister experienced this while she was pregnant. I don't remember what it was but it was harmless. I would ask your dr about it at your next appointment just to be sure though.