Husband not putting in thr effort

My husband says he really wants another baby but i just don't feel like he's trying very hard! whenever my ovulation week comes around he always tells me how 'unromantic' I am being like I'm just trying to get sex but he doesn't really put in any effort. we have been trying for 5 months now and i think if I carries on like this its going to take forever! I have asked if he is ready for another, perhaps he isn't trying because she doesn't want a baby but he tells me that he really does and it'll just happen. How can I make it more exciting so he doesn't think I'm just 'milking him' to use his phrase!??