Yeah I wouldn't tell her either.
This is what I did, I was going on a long low dose cycle and half way through it I told her that I would be starting. Sh said she was cool with it...... but when ever I got upset, which is very rarely by the way, guess what she would throw right back in my face, "well maybe if you were'nt stick'n yourself with that shit then maybe you wouldn't be this pissed off" eat shit, so just becuase I juiced I wasn't allowed to get mad. I don't care how much you think you like your chick, or how good of a girl you think she is, there is just some shit you don't let her know.
-but alot of guys think they have the best girlfriend ever, and they are going to disagree with my statement and tell me about trust and honesty and all that other fuzzy feelin heart warming stuff, so I guess there is not golden answer to this question. All that is certain is that your taking a risk telling her, and if she never throws it your face and keeps her promise then lucky you be thankful. Just keep in mind that everybody thought that their girlfriend was honest and trustworthy with that info, and a lot of those guys had it blow up in their face.
-wheeewwww, just had to vent thanx guys.