Dying your hair?

I'm almost 16 weeks pregnant, and really missing my blonde hair.. So I asked my aunt if she would put highlights in my hair (she's a nurse and said it'd be okay and wouldn't harm the baby). She would use the cap, so the bleach wouldn't touch my scalp, and she said she would put a bag over my head after she's done so I wouldn't breathe in the bleach.. Do you ladies think it'd be okay if I got highlights while he pregnant? Has anyone else gotten highlights or dyed their hair while pregnant?