It's possible that there is a Raven and Beast Boy pregnant fanfic. The Teen Titans fandom is quite large and diverse, with fans exploring various storylines. But finding it could be a bit of a challenge. You may need to use specific search terms on fanfic platforms. Also, remember that fanfics can range in quality and adherence to the original characters' personalities.
There's also a fanfic that delves into the challenges they face. Like how Raven's powers might be affected by her pregnancy. It shows Beast Boy trying his best to understand her and help her control her powers while also preparing for their new family member. It's a really interesting take on their relationship.
One plot idea could be that Raven discovers she's pregnant and is initially in denial. She tries to hide it from the rest of the Teen Titans, especially Beast Boy, because she's afraid of how he'll react. Another could be a more comical take where Beast Boy accidentally finds out before Raven has a chance to tell him, and he goes into over - protective mode immediately. Maybe he starts reading every pregnancy book he can find and trying to cook special healthy meals for Raven, much to her annoyance at first.
Perhaps in the fanfiction, the pregnancy could be a result of some sort of magical or alien interference. This would add an extra layer of mystery and adventure. They would then have to not only deal with the pregnancy itself but also figure out what caused it and if there are any hidden dangers or powers associated with the baby due to this strange origin.
A good fanfiction in this case would also involve world - building. Since they are superheroes, think about how the world they live in will react to their situation. Will there be any laws or regulations regarding superhuman pregnancies? How will the media in their world cover it? You can also add elements of conflict, such as an enemy trying to take advantage of Raven's weakened state during pregnancy or Beast Boy being distracted from his duties to protect his family. All these aspects combined can make for a great Raven x Beast Boy pregnant fanfiction.
A fanfiction could also focus on their relationships outside of being superheroes. They could be having a normal day at the Tower, just hanging out. Starfire could be trying to cook something new from her home planet, Raven could be reading a book in the corner, and Beast Boy could be cracking jokes, which at first annoys Raven but then she starts to laugh.
One key element is the relationship dynamic. Their relationship has to change and grow with the new situation of Raven being pregnant. For example, Beast Boy might become more protective and Raven might become more reliant on him in some ways.
Some Tumblr blogs might also have such fanfictions. Tumblr has a vibrant fan community, and users often share their own writings or reblog interesting fanfictions. You can search for relevant tags like #BeastBoyRaven #PregnancyFanfiction to see if there are any posts.
Raven and Beast Boy's relationship status varies in the comics. Sometimes they have a romantic connection, but it's not a constant throughout all comic runs.