It may not be anything, a friend of mine was telling me the other day, I dont really know how to explain it but ill do my best. That if u stress about trying to have a child ur body sort of shuts down and creates a barrier that wont let the little swimmers through. It may sound crazy but its not like a wall comes down but think of it in those terms only metaphorically speaking.
Just enjoy the art of love making dont let having a baby become wot sex is about. Im currently trying to have a child also and no luck yet. But I try and have sex not just on ovulation days but throughout the month, we also try and do it just b4 going to sleep that way u feel totally at ease and totally relaxed and enjoying the moment, or in the morning b4 one of us has to go to work, that way u feel good and happy and relaxed and its not just about a baby.
Other than that seeing how it has been over a year I would visit my doc and get him to run some tests if there is a prob with either one of u ur doc might no how to fix it or at least offer a solution this way u will no either way.
From someone who cant wait to have a jellybean all of their own