Crest White Strips, safe or not?

I'm 14 weeks pregnant, and wondering if Crest White Strips are safe during pregnancy?   I figured they aren't but asked around and keep getting mixed reviews and can't get into my dentist office for another 3 months, if anyone knows FOR SURE please let me know something.  

i read any teeth whitner isnt safe while pregnant i wouldnt risk it!

I don't think they are. I'm thinking when I used them that they said something on the box about not to use during pregnancy

Anytime I got mixed reviews about something, I chose to err on the side of caution.

i started to use them wen i was pregnant but stopped wen i realized it might not be safe, i dont know if it really is or not tho :-/

Thanks for the replies girls! I don't wanna risk it but I've used them once before getting pregnant and was also thinking on the inside it said don't use while pregnant! I went to the baby doctor today and overheard two women talking about how they were using them and got an OK from their doctor so I had to question it!