Hair color not turning out?

LovinLife33

Hi all, I was talking to my mom and telling her I was finally going to get my hair done, goodbye grays! She had said not to do it because it can turn out completely different when pregnant. That the color won't take the same way. I am thinking this is not true, but thought I'd ask before coming home with purple hair. :. Oh and it is a dye job not highlights she was talking about. Thanks for your advice!