One of about 4 Gundam characters to be seen visibly* pregnant within the franchise's "canon"** history.
First was Marbet from Victory, pregnant in the epilogue.
Second was Aina from 08th- again, pregnant in the epilogue.
Third was, and we're doing a hefty skip here... this very character, Kun Soon. Again, the epilogue.
lastly was Merribit Stapleton from IBO, again in the epilogue.
Because every last one of these pregnancies is to simply indicate a 'physical' timeskip, as Gundam stories are really truly connected like this.
*Technically, the first pregnant Gundam character on screen was Fraw Bow in Zeta- but at six months in the belly isn't *that* big, and besides that she was wearing a fairly loose outfit
**Canon as a term doesn't really exist in Japan. This is why you get all the throwaway movies from franchises like Naruto and Dragonball.
As of SEED, Sunrise has a three-tiered approach, "White, Grey, Black".
>White is the Main Product, the mainline anime. It takes precedence over Everything- this is why Sunrise touts Suletta as the first female protag, even though Christina from War in the pocket is right there.
>Grey is the Secondary Material- the OVAs, the Mangas, and Novels, and vidya adaptations.
>Black is tertiary stuff, and the closest thing to "non-canon" you can get in a place where "canon" doesn't really exist. Things like Gihren's Greed belongs here.