Me and my boyfriend have been dating online for 3 years now and we want to have kids?

We met on line on this virtual website in 2008 and have our own house and have a stable relationship, both of us have jobs.. I work as a teacher and he is a police officer so we both are very important people to the virtual community, but now we are feeling broody and really want to start a family.. how can I get pregnant? We've been trying for 6 months now but I don't think it's working, what can I do I am really starting to think there is something wrong with one of us?