No, I doubt there would be any possibility that coconut water could harm you, except if possibly you were diabetic, then there is a higher sugar content in CW than lets say...Normal water!
Some raw foodists drink coconut water exclusively, I have heard. They cut the coconuts open and drink the water, but what we buy in tetra packs is basically the same, just pasturized and heated.
I've drank coconut water every day of this whole pregnancy, and we are doing fine!
Midwife mama to DD1 (4.5) and DD2 (1.5)