omegaverse shower thought

Sorry if somebody already asked this but i just finished reading blood link. It's the first omegaverse story i read so theres this question im wondering about- if the ukes give birth out of their butts what if they need to poop..? Does the baby get poop stains on them? Does the poop come out from the same hole as the baby? Are there two different holes in the butt for giving birth and pooping? Just- how???