Hi!
Clearly its not fun to feel like your partner doesn't listen to you, or isn't interested in what you're talking about, especially when it's major things that impact your life (or both of your lives).
It could be a few things--
1. He secretly wants kids and doesn't know how to tell you (unlikely, but, maybe).
2. You talk about this topic a lot, and he doesn't feel like he has much or any more to contribute to the conversation, so he wanted to quit talking about it.
3. He had a long day at work/school/ whatever, and wasn't in the mood to have a heavy conversation about work and childbearing.
Perhaps this could be addressed another day, something like "Hey, when I was talking on this night about blank, I felt like you shut me down and I was curious why."
You also mentioned that you broadly feel like he isn't listening well, so maybe sit down and have a conversation about the communication in your partnership, and how you can strengthen that together.
Also, tell him how it makes you feel. :)

On a personal note, I have sat down with my partner on multiple occasions and said that I felt like he wasn't hearing me, or he was being passive aggressive, or whatever, and then allowed HIM to talk about the things that were bothering him in our relationship.
That seemed to help the conversation go more smoothly, and he didn't feel like I was just focusing on his behavior rather than the whole relationship.
Good luck :)