The goal is to get all main girls (girls with a card in the heart thingie) and most side girls (girls that had more than one sex scene) preggers at some point later in the game.
Of course, there are some exceptions due to lore.
And if we’re being realistic, Arc may have to trim down the final list.
But main girls are pretty much guaranteed. With the exception of Roxy and Qarinah, for lore reasons.