Pregnancy is a separate kink, yes, but I suspect the people in this thread who enjoy stories about pregnant mothers and sons are especially interested in incestuous pregnancy. Which may not be your kink, but definitely fits into the category this thread is intended for.
Not to mention, this is a Klrxo thread. Like 80% of her(?) stories have a mother being impregnated by her son. Possibly a higher percentage.
Pregnancy isn't really one of my kinks, although I don't mind it, and it sometimes adds heat. For instance, I'd suggest you go to Literotica and check out stories from
https://www.literotica.com/authors/WritingwhatIlike/works/stories . Especially Jen's Trip to the Beach, and Sam and Jake. But most of his stories are great, and incredibly hot, though Cabin Blues and Jane Pays It Forward aren't my cuppa. Those two stories changed my perspective on the subject (Jen's Trip and Sam and Jake). Just a suggestion.