Don't drink more than two cups of coffee a day
Are you one of those people that is not themselves until they have their coffee in the morning? How many cups do you need to have before you have the energy to face the day? If the answer is two or fewer, then it is not a problem, as fertility seems to be unaffected by under 200 milligrams of caffeine per day. However, going over those two cups could begin to impact your chances to conceive, and you do not want to place yourself at any sort of disadvantage when it comes to the possibility of getting pregnant.
The science surrounding the exact amount of caffeine your body can take before its ability to conceive is a bit vague at the moment, but until further research is produced, you should stick to the amount that is known to be safe - no more than two cups per day.