One common theme is the struggle between love and the dark side. Darth Vader is on the path of the dark side, but his love for Padme and their unborn child might create an internal conflict. Another theme could be protection, as they would need to protect their family in a dangerous galaxy filled with enemies.
There are quite a few fanfics out there on this topic. You can start by looking on popular fanfic websites like Archive of Our Own. Some might explore the complex relationship between Padme and Vader in this unique scenario, delving into how their story could have been different if Padme was pregnant and they had to face the challenges together, both as a couple and in the context of the Star Wars universe.
A possible plot could be that Padme fakes her death as in the original story, but Vader discovers she is alive and pregnant. He then decides to break away from the Empire to start a new life with her and their child, but they must evade the Empire's forces and Vader has to come to terms with his new identity outside of the Sith.
At first, it might be full of tension. Vader is now a dark figure, but Padme's pregnancy could be a catalyst for change. He might start to show moments of his old self, Anakin, and they could gradually re - connect on an emotional level.
The idea of redemption is a big one. Darth Vader's redemption at the end of Return of the Jedi is a powerful moment, and fanfics often expand on this. They might explore what led to his final choice, or how his family influenced his decision. Additionally, the exploration of the Force and how it connects all these characters is another common theme. It could be about how Luke and Leia develop their Force abilities differently, or how Anakin's relationship with the Force changed over time.
One possible plotline could be Padme hiding her pregnancy from the Jedi Council. Another could be Darth Vader finding out about the pregnancy and struggling between his loyalty to the Sith and his love for Padme and their unborn child. Or perhaps Padme trying to find a way to raise the child away from the dark side's influence.
Power is a common theme. Vader's already immense power in the Star Wars universe gets juxtaposed with the powers in other fictional worlds he crosses into. For example, if he crosses into a world with magic, how does his Force - based power compare?
Power is a common theme. Female characters in these fanfics often strive for power, either in the shadow of Vader or against him. They might be inspired by his strength or seek to overcome it.
The main characters are obviously Darth Vader and Padme. But often, other characters from the Star Wars universe can also play important roles. For example, Obi - Wan Kenobi might be involved as he was close to both of them. Or Palpatine, since he had a big influence on Vader's turn to the dark side and his relationship with Padme could be explored in relation to the pregnancy.
One common theme could be the challenges Padme faces while pregnant in the midst of the political turmoil in the Star Wars universe. Another might be her relationship with Anakin during this time and how it evolves.
Often, the theme of motherhood and how Padme prepares for the arrival of her child is explored. This might include her thoughts on raising a child in a galaxy filled with conflict. Also, there could be themes related to the protection of her unborn child from the various threats in the Star Wars world.