You're treading a fine line. For some, abstinence is the solution. For others, they evaluate their risks, the benefit from the poor (90%) effectiveness then go out and get it anyway or some other disease. Give parents ALL the information, not just the "right" (i.e. politically correct) information.
As I told, if you think that teens won't have sex because their parents tell them, then I have a bridge to sell you in Brooklyn... Cheap...