Pregnancy would create too many problems, it would become even more difficult to manage all the storylines. Already in the past there was a path in which Adele fired MC and eliminated it because it was too much.
the game is based on a storyline that is immutable, things that happen to the characters, that happen anyway, whatever you decide to do. For example Meadow blackmailing Bernie at the beginning or the end of the relationship between Adele and Gary. The amount of choices that could have a pregnancy is too great, then it must be multiplied to all the possible storylines of the other characters ... Not possible for this game