IGN: Speaking of parents, my mind goes to wondering if someone, maybe multiple someones, might come down from the Ark with a child in tow?
Rothenberg: Yeah, well, you know there’s not much you can do when you’re sitting in space for five years. I do think having a child up there would make surviving infinitely harder. Much like birth rates were closely monitored on the Ark prior to the series starting, that’s not a burden they want to take on. Not that they won’t and I’m not saying one way or another, but producing a show with a bunch of kids is a pain in the butt too [Laughs] so we wouldn’t want to use too many of them.
~ from IGN’s postmortem interview
To me this sounds like there won’t be space babies and he gave the reason I was thinking about too. The logical one.