Yes, Sammy getting creampied a certain number of times triggers this state. This is a dynamic of the game that I hope Sam_Tail changes at some point because as things stand, the circumstances of the creampie don't matter, only that it happened. It could be from Sammy asking one of her customers at the bar to cum inside or one of the bullies coming inside when they rape her. Both are counted when determining whether she wants to become pregnant. Frankly, I think she should be horrified at worst, and reluctantly accepting at best upon learning that she's pregnant with her rapist's child.
Even with this dynamic in play, I still have a lot of fun playing this game and will continue to play regardless.