Nuvaring rash on partner?

I have been on the nuvaring for almost a year. I love it. I have suffered no side effects. However, my new partner may be experiencing something. Both times we have slept together, he has developed a rash the following day. He has had it check out and confirmed that it is not an STD. It seems to be some kind of allergic reaction. Could it be the nuvaring? I called my doctor, but she hasn't called me back yet.