As a teacher if I see any injuries that could be self inflicted such as cutting I am bound by law to contact CPS. Depending on the severity of it I could contact the parents first, or ask the child themselves what has been happening. It's a hard choice to make most of the time because if the parent already knows and they haven't reported it CPS is going to want to know why and probably remove the child from the home for observation and counseling. If the parent takes the child to the Dr. the Dr. is bound by the same laws to report the injuries to CPS. In their case though at least they can notify them that the parent brought the child in seeking help so more than likely they will be referred for counseling after an investigation which starts at the Dr.s office and then goes to the home to check out the environment. The big decider is the severity of the injuries; are they just doing small slicing for attention or actual cuts that could bleed out and might be the first or second step to suicide.
I referred a student earlier this year that came in wearing long sleeves in 100 degree weather at the end of August. I kept watching her to see if she pulled up her sleeves, rubbed her arms or anything. My first thought with her was someone grabbing and bruising her; until a student told me she saw cuts on her arms in the restroom. I emailed the counselor and asked her to come to my room with an administrator and someone to watch my class. We took her to the nurses office and asked her to push up her sleeves. She had red slices all over her arms on the bottom though, not on top, so if she had her arms in her lap or on the table they would be hard to see. We asked what was going on, she told us she was upset over her Dad's new girl friend and that the girl friend did it too. Since there were obvious injuries we called CPS, then called the mom who she lived with and told her what was happening. We also had to notify the Sheriff's Office so they could come to the school in case the mom got upset and tried to remove her before CPS arrived. The mom didn't know, she was pretty upset over the dad's GF too because they had just separated. CPS found no signs she was in danger at home from anyone other than herself and she was referred for counseling, the parents were referred for family counseling.
In a different case I had a girl who wore a ton of bracelets on both arms, and kept prying the metal clip off of her pens and I kept seeing her pushing it between her bracelets. When we went to the restroom I took her into the staff lounge and told her to take off the bracelets. She refused so I took her to the office and told her flat out I was calling CPS, the SO and her mom because I thought she was cutting herself. She took off the bracelets, it was horrible! She had deep gouges in her skin, cuts that she sewed up herself with sewing thread! Totally different case. We also found out that mom had moved out and she was living with her 17 and 18 year old sisters and no parent. The sisters had serious issues and the cutting was a group thing, they helped sew other up. She was removed and put into in-house counseling at a live in facility.
No matter what, if you suspect someone is cutting themselves report it to CPS. The parents won't get in trouble unless they knew about it and didn't report it, but at least it will start the ball in motion to get the child help before they accidentally or purposely cut a vein.