Goodness, where to even begin? Maybe here...

https://www.wired.com/2009/08/spacebabies/

We've never even successfully raised a mouse in space.

Oh, you're talking about extraterrestrial reproduction being intractable. Sure. I have no view on this scientifically. That won't stop people from trying. And I'd assume there's a massive difference between zero g and 0.4g.

> That won't stop people from trying.

Or, what I consider more likely, people not trying but nature, um, finding a way. None of the common prevention methods is 100%.

Maybe. We have zero data about this.

> have zero data about this

I agree with you as much as I am certain that data have close to no consequence for the people making the decision.