I am sure it will be fine. Most hairdressers don't use ammonia base colors anymore. I dyed my hair with all three pregnancies.
DH Paul 34
DD1 Victoria 6 July 2006
DD2 Sarah 2 Feb 2011
DS1 Theodore July 2013
Married Aug 3, 2002
I do it myself... I have annoying curly hair and pay way too much for haircuts with curl specialists so I do my own color. My hair dresser taught me that at home dye is just as good as long as you follow up immediately with a deep conditioning treatment. So now I do it myself and save a ton if money (which I spend on the haircuts... Sigh...). My concern is more breathing it in when I'm in the bathroom than anything else. I'm already staining furniture this week and I'm concerned about more chemicals I guess.
(I wear a mask to stain and take regular breaks).