On the rare occasions I have felt it would be helpful to give this information in direct response to a stated problem, I try to say something along the lines of "I'm so sorry it worked out this way for you. I'm sorry that your doctor didn't know [xyz]. We depend on our doctors and when they let us down there's nothing we can do about it. It might help other women if you could write to the practice saying [xyz] so that they can train up on it."

Blame the advice-giver, not the frightened, sleep-deprived, hormonal mother who took it.