So, when do the mandatory sterilizations start?

[loyalsister]

14. You nailed it

It's positive eugenics. Increasing population contributions from desireables complements the strategy to reduce that of undesirable genetic influences.

It is laid out in How All Politics Became Reproductive Politics, though not explicitly connected to eugenics. One thing it clarified is the timeline for the hostility towards social programs and how any question of the morality of letting people starve was counterbalanced with a sense of moral superiority in fetus protection.