tests could include any of the following......bloodtests, usually at varying days in your cycle to see what your hormone levels are doing and to rule out any thing there, a simple internal ultrasound to start to see if anything like ovarian cysts or anything "barks" at them as being abornmal.

Next stage is usually a HSG where they inject some dye into the fallopian tubes while doing an ultrasound to check if the tubes are clear.

The next stage up would possibly be a laparoscopy but that would only be in some instances depending on what they find in the initial tests.

What would help the docs is if you had at least a couple of months of temp charting to show them so they can see when and if you ovulate and that sort fo thing...it will guide them as to what tests to do and also what treatments. If they find you are not ovulating correctly the treatment may be as simple as clomid tablets to stimulate better ovulation. The more information you can provide them with the easier it willbe for them to find out hopefully what the issue is.....