Is it wrong....

So my fiance and I are trying to concieve, but I dont want to be pregnant for my wedding. It just not in my vision. I know it sounds a little vain, but i dont want to pregnant in my wedding photos. So I calculated the what month to get pregnant by in order to give my about 4 months to get back in shape and have my dress altered, if needed, once I find a dress. Is it wrong that I'm kind of putting a deadline on when to get pregnant? I told my fiance and he is fine with it cause I told him we can start trying again the month of the wedding.