Ttc and dying your hair

Marissa • 37 y/o. PCOS & thin lining. TTC #1. Ectopic March 2015. 1st IVF FET 2/19/16=BFN. 2nd FET 4/1/16=MC. 3rd FET 8/5/16=BFP.
Is it ok to dye your hair when TTC or are pregnant?