Is it safe to get Botox at 15 weeks pregnant?

Hi I usually get masseter botox for my bruxism and TMJ. It also helps my face get a slimmer appearance because I generally have a v square jaw. The affect of my last botox are wearing off now & my TMJ's getting worse. Im also 15wks pregnant & v confused if I should proceed with it or not. The studies show it doesnt cross the placenta or enter bloodstream so it shouldnt be a problem but the risks are unknown & im v scared as to what to do. I wanna go for it but im scared