One possible plot twist could be that the pregnancy was a result of some scientific experiment gone wrong. Maybe Moriarty had a hand in it as part of his grand scheme to mess with Sherlock's mind. Another could be that Molly discovers she's pregnant but Sherlock is in the middle of a very dangerous case and she has to struggle to keep the news from him while also dealing with the changes in her body.
Well, it could be that the pregnancy is part of a prophecy or an ancient family curse. Sherlock, being the logical one, would initially reject the idea but as the story progresses, he starts to see strange coincidences that make him believe it might be true. And Molly would be caught between her scientific mind and the strange events surrounding her pregnancy.
Perhaps a plot twist is that the pregnancy is not what it seems. It could be a false positive due to some rare medical condition that Molly has. Or, there could be a twin situation where they initially only detect one baby but later find out there are two, which throws their whole plan for the future into chaos.
One possible plot twist could be that the father of the baby is not who everyone initially thinks. Maybe there's a secret admirer or an old acquaintance who turns out to be the father. Another plot twist could be related to the safety of the pregnancy. For example, there could be a new threat in the world she lives in that specifically targets pregnant women. Or perhaps, Michonne discovers some special powers or abilities that are awakened during her pregnancy, which is completely unexpected and changes the course of the story.
Yes, there are many Sherlock Molly pregnant fanfictions. Writers like to create this scenario to see how the characters, especially Sherlock, will react to such a life - changing event. It can also be a way to explore Molly's character more deeply, as she navigates motherhood and her relationship with Sherlock.
Perhaps in the fanfiction, the pregnancy is a result of some kind of experiment gone wrong. Sherlock then has to use his brilliant mind to figure out how to ensure the health of both Molly and the baby. He might have to face his own fears about becoming a father and how it will change his life and relationship with Molly.
One interesting plot twist could be that Sherlock initially doesn't believe he's the father and tries to use his deductive skills to disprove it, only to find out he was wrong all along. Another could be that Molly tries to keep the pregnancy a secret from Sherlock at first, but then circumstances force her to reveal it in a very dramatic way, like during a dangerous case. And sometimes, there might be a plot twist where other characters, like Mycroft, try to interfere with the situation for their own reasons, either to protect Sherlock or because of some secret agenda they have regarding the potential child.
Another plot twist could be that the father of the baby is not who they initially thought. This would create a huge amount of drama and relationship turmoil. It could also lead to a search for the real father and a battle against whoever was trying to deceive them about the pregnancy.
Well, a plot twist could be that the baby has some unexpected powers. Since Klaus is a hybrid and Elena has her own unique connection to the supernatural world, the baby could inherit a combination of powers that no one has seen before. It could also be that Elena discovers she's pregnant but then loses the baby due to some dark magic, which leads to Klaus going on a rampage. Then, later, it turns out the baby is still alive but has been hidden away by a secret group who wants to use it for their own ends.
The plot twist could be that Kol and Davina find out that the pregnancy is part of a prophecy. However, the prophecy has been misinterpreted by many. They initially think it's a good thing, but as they dig deeper, they realize that there are dark forces at work trying to use the baby for their own evil purposes. So they have to fight against these forces to protect their unborn child and their future together.
One possible plot twist could be that they initially think they are having one baby but find out it's twins. This would add an element of surprise and more challenges for them in the story.
One possible plot twist could be that they face opposition from their respective families or groups. Maybe Ahsoka's Jedi Order is against it due to their code. Another could be that there are complications during the pregnancy that force them to seek help from unlikely sources. For example, they might have to turn to an old enemy who has medical knowledge.
One possible plot twist could be that they discover the pregnancy is part of a time - altered event. Maybe some villain from the future has meddled with their timelines to ensure the pregnancy for some devious plan. Another could be that during the pregnancy, they find out that the baby has some extraordinary powers related to time travel, which brings both excitement and fear.