Katniss would likely become more protective. Her natural instinct to survive would be amplified by the need to protect her unborn child. This could make her more cautious in her actions in the arena, but also more fierce when directly threatened.
One possible storyline could be that Katniss discovers she is pregnant just before entering the arena. She then has to fight not only for her own survival but also for the unborn child. She might form unexpected alliances with other tributes who decide to protect her because of her condition.
Well, if Katniss was pregnant in fanfiction, it could bring a lot of emotional turmoil and difficult decisions. It might also affect her relationships with other characters and how they respond to her situation.
In some Catching Fire fanfictions, Katniss might be depicted as pregnant. Fanfiction allows for a lot of creative interpretations of the story and characters. However, in the original Catching Fire book, there is no such indication.
It could add a whole new layer of complexity to the story. Maybe it would force her to make even tougher choices to protect her child in the dystopian world.
Katniss copes in multiple ways. She has to be strong for herself, Peeta, and the unborn child. Emotionally, she might bottle up some of her feelings at first, but as time goes on, she realizes she needs to let them out. She could start writing in a journal about her experiences, fears, and hopes. Physically, she takes care of herself as best as she can in the difficult situation, eating whatever nutritious food she can find and getting enough rest when possible. Socially, she tries to keep a small circle of people around her who can support her, and she also tries to slowly re - introduce Peeta to those who care about him in a way that won't trigger his hijacked state.
Their relationship would likely become more intense. With a baby on the way, they'd have to rely on each other more. Gale might become more protective of Katniss, and Katniss would have to trust Gale in new ways.
She might struggle at first. Katniss has always been a fighter, and motherhood is a whole new territory for her. She would likely be very worried about not being a good enough mother. However, with the support of Peeta and her friends, she would gradually learn to balance her new role. She would also use her strong will and determination to provide the best for her child, making sure they have a better life than she did growing up in District 12.