There are many different tests for each of the different STIs. There is not one test that will screen for all STIs. Some STIs are hard to test for if you do not have any symptoms. Some STIs can be tested through simple blood work or a urine test; some can only be tested for through culturing body fluid from the penis, vagina or open sore on the body. When you go in for testing, it is important to ask your health care provider which tests will be done and which will not. Sometimes, weeks or months need to pass to give your body enough time to develop antibodies that will show up in a test, indicating you have a particular STI.