TTC / Early pregnancy - herbal teas to avoid?

[floraflora]

Does anyone know if there is anything in the herbal tea department that one shouldn't drink if TTC?
Equally, I drink a herbal blend with a small percentage of blackberry leaves in it - do they have the same effect as raspberry leaf tea, i.e. can bring on labour?
AND, are there herbal teas that help with conception?
(Have posted this in the conception section too...)
Thanks.

I just read somewhere that green tea should be avoided when TTC and in the first trimester...i never knew that but im sure i read it somewhere on here!