the mirena is an intrauterine system that steadily releases levonorgestrel which is a synthetic form of the female hormone progesterone. (it is not the same as the coil). because it releases the levo, it may take some time before your body's hormone levels return to normal. the length of time can differ between women, but it has only been a month, give it time. try to relax as stress wont help matters, if possible, try to almost forget about trying to get pregnant and just have fun, keep yourself busy, exercise, eat well to promote a healthy body and just let nature take its course. dont forget the folic acid, its recommended that folic acid should be taken for 12 weeks prior to conception to prepare the uterus, so start taking that, and your hormone levels will hopefully return to normal by the time you've finished taking them. take care and best of luck to you xx