Yes, there are likely some out there. You can try searching on fanfiction websites like FanFiction.net or Archive of Our Own. Just type in 'Bella and Stefan pregnant' in the search bar and see what comes up.
Yes, in many fanfictions, Bella is often written as Stefan's mate. Writers like to create crossovers between different fictional universes and explore new relationships. It adds an interesting twist to the characters' stories.
There might be a fanfiction where Bella and Stefan are both at a supernatural convention. They initially mistake each other for someone else. As they start talking, they realize they have a lot in common in terms of dealing with the supernatural world around them. This leads to a series of adventures together, and they gradually fall in love.
One reason could be the allure of the 'forbidden love' aspect. Stefan is a vampire and Bella has her own complex relationship with vampires in her original story. This makes their potential relationship full of tension.
It could be that an old enemy of Stefan's family decides to target Bella as a way to get back at Stefan. This enemy might be another vampire clan or a supernatural being with a long - standing grudge. They would do everything in their power to disrupt the relationship between Bella and Stefan, causing all sorts of problems and conflicts for the two of them in the fanfiction.
Love and commitment are common themes. Since they are married, the stories often explore how they stay true to each other. For example, in many of these fanfictions, they face external threats but their love for each other remains strong.
Another possible fanfiction could be about Stefan teaching Bella some vampire self - defense techniques. Since Bella has been involved with vampires in her own story, Stefan decides to help her become more capable of protecting herself. This leads to a series of training sessions that also bring them closer together, as they share their life stories during the breaks.
Well, often there are themes related to the anticipation and excitement of new life. There may also be themes of protection, like how Stefan will protect Bella and their unborn child. And sometimes, there are themes of conflict, for example, if their relationship was not initially accepted by others, the pregnancy could add another layer of complication to that. Also, the theme of personal growth for both Bella and Stefan as they prepare to become parents can be quite common in such fanfictions.
Often, in these fanfictions, other vampires can be the main antagonists. For example, a jealous vampire who wants Stefan for herself might see Bella as a threat and try to drive them apart.
One possibility is that the baby has some special powers. In the fanfiction, this could lead to a whole new set of adventures. Bella and Stefan could be on a journey to understand and control these powers while also dealing with their own relationship and the new family dynamic.