I bought this nifty thing from Priceline that is a small battery operated razor thingy for "ladies" only it doesn't leave stubble. It was around $14.00. I've found it quite effective for facial hair removal. I also like Veet for the face. It's very mild and shouldn't be a problem. Might be worth considering if you are worried about bleach.

Tulip, I also didn't do my roots for the first trimester. I was shocked at how much grey there was. I hadn't had a real good look at my actual hair colour for about seven years!