What can cause cervical intraepithelial neoplasia (cin)?

HPV. Cin is a precancerous condition of the cervix. It is almost always caused by the human papilloma virus (genital warts). There are several strains of this virus. Some of them cause actual warts, and others don't cause warts but insert their dna into the host (that means you), causing cellular changes that can go on to become cervical cancer.