NoobAI trained LoRA, can work with Illustrious but result may vary.
An alternate training result from my loose pregnant clothing lora, main goal is to remove annoying middle vertical seams in clothes when pregnant woman generated with covered bellies. I add bare belly without linea nigra images in the dataset, so it also remove it in bare bellies to make it looks cleaner. belly button is also become less popped out. It become somewhat unrealistic, but it's cleaner.
No additional tags needed, I'm sure you put pregnant in the prompt.
I'm not sure how long this model can be stay on CivitAI, because the moderators, somehow the image rated as XXX and sometimes manually blocked by them. No nudity, just suggestive, of course pregnancy imply sex happened in far past, but i don't know why intercourse image are allowed but pregnancy isn't, maybe they love promiscuity but hate the consequences, like pregnancy or STDs.