
That's what was indicated. I'm thinking the mangaka changed their mind. Zero is definitely shown dying while Yuki is pregnant. Ren's quiet, sad and serious personality, along with her appearance strongly resembling Zero fits with this too. Now that the child isn't Ren, it means Yuki was going to have another child. But then what happened to it?
One of the reasons I'm going to keep reading. I hope sensei didn't just forget about it.

That's what was indicated. I'm thinking the mangaka changed their mind. Zero is definitely shown dying while Yuki is pregnant. Ren's quiet and reserved personality, along with her appearance strongly resembling Zero fits with this too. Now that the child isn't Ren, it means Yuki was going to have another child. But then what happened to it?
Wait...so Ren is a girl? My bad, thought she was he for a long time