Would you be upset if your partner said they didn’t want to watch the birth of your first child because it’s “gross”?

I’m trying to evaluate if I am being rational or not. My boyfriend has said that he doesn’t want to see the birth of our son. He wants to be there holding my hand supporting me but he finds the actual birth idea gross. I think it’s immature and I’m personally offended. I’m also unsure if that’s pregnancy hormones and if I’m asking too much. He’s incredibly supportive in every way possible so I’m unsure if I’m just expecting him to have the same feelings as I do. We tried for this baby for over a year so I expect him to want to see the first moment of his life outside of me. I understand it’s gnarly but it’s also beautiful. Is this not common for men to see? Also, I’m only 17 weeks along so his mind might change.