Here is hoping the add more pregnancy content and systems with it in the future! Would love to see Anna pregnant with a lot of scenes and be able to take photos of her while pregnant down in the studio with her outfits!
Pregnancy will be event based like Evelyn's current pregnancy route and believe will funnel into endings.
A full impregnation and pregnancy system would take up too much development time and result with having to create new interactive elements and modified sprites and CGs
You will see Anna pregnant, but just limit your imagination or hope for a community mod 😉