Yeah, you would have to alter yourself to become some sort of twisted brood mother that lays many eggs.

Surely a mistress of Life magic would be able to cast spells to ovulate as large a group of ova in one cycle as she liked, selectively fertilize each one using a handy supply of men or the necessary fluids, and teleport the individual embryos into host mothers. No need to go all insectoid or disrupt more than one menstrual cycle...

Well, I was mostly being silly because I don't expect to see much reproduction-oriented magic in the initial game. But yea, a female sovereign with Life magic strenght should be able to make herself an 'octomom plus,' the plus being she can outsource some or all of the gestation work. Not the best way to build a loving family, probably, but could provide an edge in a dynastic competition...

I'm sure all this is already decided, but I was thinking that one way you can fictionally avoid all these breeding mechanics, is to have the channeler not be the actual sovereign, but actually a respected, immortal servant of a normal royal house, kindof like a Merlin type character. The kings think that the struggle is all about them, but really it's a battle between wizards.

If the channeler needs a king for legitimacy, then all of a sudden you have a reason for sons, daughters etc.