I believe that Fanny is prescribed some type of pills that mimics pregnancy by releasing hormones into the body. This may be prescribed as it allows women who want the positive feelings of pregnancy without bearing of children. If a woman can take medicine that mimics pregnancy, the body wont feel the need to be pregnant for real, which benefits the World state.
Evolution theory is a shortened form of the term "theory of evolution by natural selection," which was proposed in the 19th century by Charles Darwin and Alfred Russel Wallace.
