It's common for men and women to have a STD without any symptoms. So you might not know you have one. Even if you don't have symptoms, you are still contagious and can pass the disease onto your partner. STDs, including the ones that don't cause symptoms, can cause serious problems with your health later on. They can cause PID (pelvic inflammatory disease), infertility and even cervical cancer . STD testing is recommended to anyone who has had sexual relations with one or more partner. It is even more important to get tested if you have one or more signs of an STD.