The closest natural phrasing to what you have written is
Ladies are advised not to view these pictures as they may depict violence.
This sounds very sexist, though, and I'm not very sensitive to sexism. I have used the word "advise" because "instruct" implies that you are in a position to order someone not to view something, which seems very unlikely to me.
There are a few standard ways of saying something like this, which you see all over:
These images may depict graphic violence. Viewer discretion is advised.
Warning: These images may depict graphic violence, which some viewers may find disturbing.