Probably one of the most frustrating medical terms ever, "unexplained infertility" is used to describe a couple who have been trying to conceive for a year or more, and despite undergoing most or all of the tests listed in It's Been A While, no reason can be found to explain why the female partner hasn't become pregnant. What's more, medical specialists are often unable to give firm guidelines about whether conception is ever likely, how much longer it may take, and whether assisted conception should be considered immediately or in the longer term.
If you've been given this very woolly diagnosis, the first thing to do is (try) and be reassured that the absence of any definite problem means you will hopefully get pregnant at some point. After all, as we explain in Positive Attitude, it is a minority that will literally never do so. And if you're not doing so already, it's worth trying some of the recommendations in Improving Your Chances, particularly some of the Alternative Approaches. Last but not least, you or your specialist may eventually decide that Assisted Conception may be a solution once all natural methods have been exhausted, but it's important not to rush in to this too quickly as technically the success rates are relatively low and the costs are high; practicalities which are often overlooked in the desire to feel that you are taking positive steps.