I'm 33, FI is 40. We are 99.9% sure we are not having children. We were at a party this weekend. These are the conversations I got to have.
Lady: Congrats on getting engaged!
Me: Thanks!
Lady: (her grandkids were at the party and were closeby) I guess you'll be having some of these right away! 
Me: No, I don't think we're having children. 
Lady: Really? Why? 
Me: Uh...
Lady: Your mom must be upset you don't want kids. 
Me: No, she's not. 
Lady: You know, your life doesn't really change THAT much when you have kids. 
Girl: Congratulations! Let me see your ring! Can you believe my oldest is 18?! I think we're going to have another baby soon. 
Me: That's great!
Girl: You'll be having kids soon too, right?
Me: No, I don't think we'll be having kids. 
Girl: Oh, really? That surprises me. 
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@_#* I'm so tired of being asked about kids. First, I have to deal with people assuming that because I'm 33, I must be desperate to pop out a baby right after we get married. Then, I have to defend my choice of not wanting children. What if I can't have children? These people don't know the intimate details of my reproductive system. Granted, the second conversation wasn't as bad as the first. But I just hate being asked about it. Just because I'm getting married doesn't mean I'm having kids! 
I made the mistake of one time telling someone we were having kids, just because I didn't feel like having to defend not having them. Someone asked and I was all, "Yup!" thinking that would be the end of the conversation and I could walk away. Then I was cornered for 30 minutes listening to stories about babies and poop and diapers and clothes and strollers and cribs. Good times!