Telling our parents about infertility

Well we are telling our parents this weekend about our infertility issues. I have no idea how we are going to do it. Since we started ttc both sets of parents have said we should wait and there's no rush. I know they we will be happy when we do get pregnant but what about now? How will they feel when there is a possibility we will never have children. I have no idea how we are going to even tell them this. we can't just be like "hey Mom and Dad so we may not ever have kids" and leave it at that. We are telling them now because if I have to have surgery to fix a septum in my uterus they need to know why I am having surgery, and we have family reunions coming up that we will definitely be asked when we are going to have babies so we need their support. How have you told your parents about your infertility?