Wow, can you get more polar opposite of CS Lewis than Margaret Atwood? Despite her protestations of not writing science fiction, her story of a dystopian future where almost all women are infertile is most assuredly of the genre. Set in a future where disease and radiation have reduced fertility to a minimum, and a fascist military theocracy has taken over America (or at least part of it). Brutal in its critique of evangelist Christianity and their view on women, Handmaid’s Tale is a harrowing read at the best of times. In it, women have essentially been reduced to chattels, and the few fertile ones assigned to high-ranking military men in order to give them children.Read about the other books on the list.
The Handmaid's Tale made Lisa Tuttle's critic's chart of the top Arthur C. Clarke Award winners.
Also see Robert Collins' top ten list of dystopian novels and Gemma Malley's top 10 list of dystopian novels for teenagers.
(h/t to Bill Crider)