How do I tell my boyfriend that I was raped?

I was raped in November of last year and I met my boyfriend in early May. I want to tell him because I trust him and don't want to keep things from him. I am scared that he'll just pity me or walk on eggshells around me. He is a really great guy and I'm probably being irrational. I don't think I have to tell him NOW, but I would like to tell him eventually. How do I do it?