I've read a great book in the late 80s or possibly early 90s, and cannot remember either the title or author. It was about the beginnings of a breakdown of society due to mass infertility ... might have been something in the water.
Society has turned into a ugly patriarchal system, with the few women who are still fertile tightly controlled, but not by governments. It's more like cult-like groups.
The main protagonist is some type of ex-solider and gets in with a group of sensible people. He has the skills to protect them and falls for a woman there. At one point they decide to have a last stand in a supermax prison. It was built but never used due to the breakdown, but turns out to be a great fortress.
During the last part of the book there is an attack by some group. The protagonist leads the defence and prevails. His girlfriend who is somewhere else during the attack later tells him how she baked a cake to keep her mind off things.
It sounds very chauvinist but is actually not and a great read. It's not "Children of Men", "The Handmaiden's Tale" or other common ones.