One challenge could be dealing with the expectations of others. The Cullens might have their own ideas about how she should handle the pregnancy, and Bella might feel pressured to conform. Additionally, she has to worry about the safety of her unborn child. There could be threats from other vampires or supernatural beings that she has to constantly be on guard against.
She could have physical discomforts like extreme fatigue and morning sickness. Also, she might worry about providing for three babies financially.
She might have physical discomfort and health issues. Also, there could be financial strains and emotional stress.
In Twilight fanfiction, Vampire Bella going to school has multiple difficulties. Firstly, her appearance. Even though she tries to blend in, her pale skin and other vampiric features might make her stand out. Secondly, her academic performance. With her new vampire - enhanced mind, she may find it hard to not seem too smart and draw unwanted attention. Thirdly, the relationships. She has to keep her distance from her old human friends in a way that doesn't seem too odd, while also dealing with any new vampire - related relationships that might form at school.
She might face the challenge of dealing with supernaturally - powered guests. For example, if a vampire guest gets angry, she could be in real danger. Also, she may have to keep the hotel clean while also hiding any signs of the supernatural activities that might occur there.
Robin could face challenges in her relationships. Her friends might have different opinions on how she should handle the pregnancy. Her partner, if there is one, might not be as ready for a baby as she is. For example, if Barney is the father, he has a history of being irresponsible, and he would need to grow up quickly, which could put a strain on their relationship.
Mabel would likely struggle with telling her family. Dipper might be shocked and not know how to react. Her parents could be disappointed or worried. She would also face challenges related to her own future plans. Maybe she had dreams of traveling or exploring more of Gravity Falls, but now she has to put those on hold for the baby. And there's always the fear of the unknown, like what if there are complications during the pregnancy or if the baby has some sort of special condition related to the strange nature of Gravity Falls.
She might face physical challenges. For instance, the long hours at the crime scene or in the lab could become exhausting more quickly due to her pregnancy. Standing for long periods or carrying heavy equipment could be difficult.
Societal and family pressures could be another big challenge. Their families might have different expectations about how they should raise the child. And in the public eye, there could be a lot of speculation and judgment, which can be difficult to handle during such a personal and vulnerable time like pregnancy.
In this fanfiction situation, a big challenge could be communication. Vegeta is not the most talkative or emotionally expressive character. So, when Bulma is pregnant and has all these hormonal changes and needs, he might struggle to communicate effectively with her. Also, they may face challenges from the Saiyan - human cultural differences. Vegeta's Saiyan upbringing has different values compared to Bulma's human family traditions, and this could cause some friction during the pregnancy.
Bella herself might struggle with her identity. She has been so caught up in the vampire world before, and now being with Jacob, a werewolf, she has to redefine who she is and where she belongs. She may also worry about how her human family and friends will react to her being with a werewolf.