Maybe an older, wiser character like Tsunade. Tsunade has a lot of experience and knowledge. She could offer medical help and also give Sakura advice on how to handle the situation. She might be able to provide a safe place for Sakura to stay during her pregnancy if needed.
Her closest friend might help her. Someone who really understands her and is willing to keep her secret. For example, Ino could be that friend. Ino has always been there for Sakura in the original story, so she could be the one to support Sakura during this difficult time.
It could be a new character introduced in the fanfiction. A kind - hearted stranger who stumbles upon Sakura's secret and decides to help her out. This person could offer practical things like a place to stay, food, and also emotional support. They might have their own reasons for helping, like they've been through a similar situation themselves.
Maybe Sakura is afraid of the reaction from her friends or family. So she decides to keep her pregnancy a secret at first. She might be worried about how people will judge her, especially if she's in a difficult situation like not being in a stable relationship.
One character could be Naruto. He might be Sakura's friend, but completely oblivious to her hidden pain. He's so focused on his own goals that he doesn't notice Sakura's struggle, which could add to her feelings of loneliness.
One possible reason for Sakura to hide her true strength in fanfiction could be for self - protection. Maybe she is in a world where showing too much power makes one a target. For example, if she is in a political intrigue - filled setting, she might keep her strength under wraps to avoid being used by various factions.
Perhaps Sakura is dealing with family issues. She could be hiding the pain of having a difficult family situation, like an overbearing parent or a family member with an illness. In the fanfiction, she might focus on her school or ninja work to distract herself from her family problems.
Sakura's friends like Naruto and Sasuke could be main characters. They might be the ones trying to find a way to save her. They could be using their skills and powers to look for a cure or a solution.
It could be Naruto. Naruto has a strong bond with Sakura and would sense that something was wrong. He'd probably track her down using his amazing sense of smell or by asking around. Once he found Sasori, Naruto would use his Rasengan and his newfound Sage Mode powers to take on Sasori and rescue Sakura.
Sasuke might also be involved in the rescue. Despite their complicated relationship, he still has some feelings for Sakura. And he wouldn't want to see her in the hands of someone like Deidara. Also, Kakashi, as their former sensei, would likely lead a rescue mission. He has the skills and experience to deal with Deidara's explosive attacks and find a way to save Sakura.
Sakura herself is obviously a main character. There could also be Naruto and Sasuke. Maybe Sakura misses her chance with Sasuke because she didn't speak up when she had the opportunity. Naruto might be involved as a friend who tries to encourage her but fails. Another character could be Kakashi, her sensei, who might have given her advice that she didn't follow, leading to her missing the chance.
One possible fanfiction could be that Sasuke returns to Konoha after a long mission. Sakura, who has been longing for his return, discovers she is pregnant. This news brings a mix of joy and worry. The village of Konoha is also excited as it means a new generation is coming. Sasuke might initially be shocked but then becomes determined to protect his family and the village.
A common plot device is the 'big reveal'. Sakura's true strength is suddenly shown in a moment of great need, like when her friends are in extreme danger. This creates a dramatic effect and often turns the tide of the story.