One storyline could be Dawson having to deal with morning sickness while on duty. She might try to hide it from her colleagues at first but then they find out and offer their support.
There could be many interesting fanfiction plots around Dawson being pregnant in 'Chicago Fire'. Maybe it could explore how she balances her job at the firehouse with her pregnancy, the support she gets from her colleagues, and the changes it brings to her relationships.
The plot might involve Dawson being initially scared to tell Casey about the pregnancy. Once she does, Casey has to deal with his own insecurities about being a father. As the pregnancy progresses, they could face criticism from some people in their lives who think they're too young or not ready. But they stay strong together, with Dawson relying on the support of the female firefighters and Casey getting advice from his male colleagues. In the end, they look forward to the birth of their baby with excitement and a bit of nervousness.
Their relationship will likely become more intimate. Casey will be more protective of Dawson, and they'll have to communicate more about their future plans. They'll be more focused on each other and the baby rather than just their own individual lives.
One possible scenario in such a fanfiction could be that Dawson gets hurt during a rescue operation. Maybe she is trapped under some debris while trying to save a victim in a burning building. Her fellow firefighters then have to race against time to get her out safely.
In a fanfic where Dawson gets hurt in Chicago Fire, it could start with a routine call that turns dangerous. Let's say there's a gas leak explosion and Dawson is caught in the blast. Her colleagues would be in a state of shock and panic. They'd quickly try to assess her injuries and get her to the hospital. At the hospital, there could be a waiting game as they all hope for her recovery. Her injury might also make her question her future in the firefighting profession. Some of her friends might encourage her to keep going while others might be more hesitant, thinking she's been through enough. This conflict among her friends and her own internal struggle could form the basis of the fanfic.
Another theme is professional growth. Fanfics might show how they learn from each other and improve their skills as firefighters. For example, Casey might teach Dawson a new technique for handling a certain type of fire, and Dawson could share her insights on dealing with victims.
She could be hurt while responding to a chemical fire. The chemicals could cause burns or respiratory problems for her. Her team would be desperate to get her the proper medical treatment, and there could be a struggle to find the right antidote or treatment method.
Common themes in 'Chicago Fire' pregnant fanfiction include the anticipation and excitement of a new life. The characters in the fanfic might be preparing for the baby, buying baby clothes, and setting up a nursery. Also, there could be themes related to health concerns. Since firefighting is a dangerous job, there might be worry about the pregnancy being affected by the work environment. And of course, relationship themes are also common, like how the pregnancy affects the relationship between the pregnant character and their partner or family members. It's a complex mix of themes that add depth to the fanfiction.
One possible storyline could be that they initially struggle to balance their dangerous jobs at the Chicago PD with the impending arrival of the baby. They might worry about how their work will affect their ability to be good parents. For example, they could face a difficult case that makes them realize they need to make some changes in their lives for the safety of their unborn child.
I'm not sure of a particular 'Chicago Fire' pregnant fanfiction off the top of my head. But generally, in such fanfictions, there could be a lot of emotional moments. Maybe a character discovers they're pregnant and has to deal with the fear of how it will impact their career in the fire department. Or perhaps it's about a couple in the show having a baby and how they prepare for it while still being involved in all the action and drama that 'Chicago Fire' is known for.