Some smaller, more niche fanfiction communities might also have such stories. You can find these by doing a general web search for 'fanfiction communities' and then exploring those to see if they have the type of Mpreg fanfiction you're looking for. It might take a bit more effort, but you could discover some unique and interesting stories this way.
One common trope is the element of surprise. The character is going about their normal life, not suspecting they are pregnant at all until something unexpected happens, like fainting or sudden abdominal pain. This builds a lot of drama and tension in the story.
One common theme is self - discovery. The characters often have to re - evaluate who they are when they find out they're pregnant. Another theme is the element of surprise. It's a shock to them and to those around them. For instance, in many stories, the friends and family are as stunned as the pregnant character.
One story is that a woman was still having what she thought were irregular periods, just a bit lighter. She was also very active and fit, so she didn't notice any significant weight gain. One day, she felt some sharp pains in her stomach and went to the hospital. To her great shock, she was about to give birth.
Well, from a medical perspective, without early detection, there's a risk of complications during childbirth. If the mother didn't know she was pregnant, she may not have adjusted her lifestyle accordingly. For example, she might have continued to smoke or drink alcohol, which is very harmful to the unborn baby. Emotionally, it can create a complex relationship between the mother and the baby initially, as she has to quickly come to terms with the new reality of being a mother when she was completely unprepared.
Common themes include the unexpectedness of it all. It's like a plot twist in the character's life. There can be themes related to health scares too. Since they didn't know they were pregnant, they might not have been taking proper care of themselves. So, dealing with potential health issues for the mother and the baby becomes a part of the story. Also, themes around new relationships or the transformation of existing relationships are common. For instance, a relationship with a partner might change completely when the pregnancy is revealed, either growing stronger or facing difficulties.
Similar symptoms from other conditions or medications. Some medical conditions can cause symptoms like nausea, bloating, and weight gain which are also pregnancy symptoms. And certain medications can have side effects that are identical to pregnancy signs. For instance, some antidepressants or drugs for hormonal disorders can make a woman think she is just having side - effects rather than being pregnant.
It could be about a character in the '50 Shades' universe who discovers she is pregnant unexpectedly. Maybe she's been so caught up in the complex relationship dynamics with Christian Grey - like the BDSM aspects and power play - that she didn't notice the signs of pregnancy at first. Then the story could explore how this changes their relationship, whether it brings them closer or causes more conflict as they both have to deal with this new situation.
Perhaps the fanfic could show the woman's journey in a '50 Shades' world while being pregnant without realizing it. She could be going through all the intense moments in the relationship, like the power play and passion, all while her body is changing due to pregnancy. And then, when she finally discovers she's pregnant, it could lead to a whole new set of conflicts and reconciliations within the relationship. There could be a lot of drama, from the woman's fear of how the man will react to the man's own insecurities about becoming a father in such a complex relationship.