There's more than one way to skin a cat, but most of the NPCs that will be pregnant will be scripted to do so. Examples of these are the fairies in the Fairy village, the Royal City Crime Lord Quest, and the School of Wizardry and Witchcraft. These alone should be enough to do the Fertility Quest, but feel free to look around and see if anyone wants a seed (or a few).
In other words: Patience padawan, for the time of the NPCs has not come yet. Not until after chapter 3 where you can wander around a whole lot more.
