Another aspect could be how they plan for the future. They might decide to move away from Mystic Falls to start a new life. This would involve leaving behind their vampire - filled world and trying to build a normal life for their baby, which is full of both difficulties and hopes.
One great 'Elena pregnant' fanfiction is 'Elena's New Chapter'. It beautifully explores how Elena's pregnancy changes her relationships with other characters. It has a really interesting plot where she discovers new sides of herself during this special time.
Another theme is self - discovery. Elena usually discovers new things about herself during pregnancy. She might find new strengths or weaknesses. In some fanfictions, she learns that she can be more independent or that she needs more support than she thought.
Yes, there are some out there. You can start by looking on popular fanfiction websites like Archive of Our Own. Just search for 'dean and elena pregnant' and you'll likely find a variety of stories with different takes on the concept.
One idea could be that Elena discovers she's pregnant during a time of relative calm in the Fast and Furious world. She then has to decide whether to tell Dom or keep it a secret for a while. Maybe she's worried about how it will affect his dangerous lifestyle.
Elena would be devastated when Damon leaves her pregnant. She has always had a complex relationship with him, and this would be a huge blow. She might isolate herself at first, not wanting to share her situation with others. But as the pregnancy progresses, she would start to realize that she has to be strong for the baby. She would draw on her inner strength and the memories of the good times she had with Damon to find the courage to face the challenges ahead. She might also experience moments of hope, thinking that Damon could come back someday, but she would not let that hope consume her and would instead focus on building a life for herself and her child.
They would likely become closer. The shared experience of having a child on the way would create a strong bond between them. Alaric would probably be very protective of Elena.
Love and family are common themes. Their love for each other deepens as they anticipate the arrival of their baby. Family also plays a big role as they think about how their families will react and how they will create a new family unit.
A great way to develop the story is to explore the medical side. Since Elena was a vampire and now is pregnant, there could be all sorts of complications. How do they find a doctor who can handle her unique situation? This could lead them on a journey to find answers and resources, which would make for an exciting plot.
The other vampire clans might be antagonists. They could see the baby as a threat to the vampire hierarchy or fear that the baby will have powers that could disrupt the balance among vampires. For example, the Originals' siblings who don't trust Kol might try to stop Elena from having the baby.