Answer:
In fact, there are two answers that would be correct, according to historical data, from the University of California, at Berkley. The first choice here is Margaret Sanger, who became the best known for her advocacy towards the distribution of birth control for women. However, there is a second woman, who came before Sanger, and who was actually the mentor of the latter. This woman was Emma Goldman.
Emma Goldman was among the first women who started the advocacy of birth control, and the right of women to control their lives and their bodies. She fought constantly against the 1873 Comstock Law, which forbade the distribution of literature on birth control, and she also campaigned incesantly against the prohibition of the use of birth control. She went to jail for the cause even, and she was the one who invited Sanger into the whole cause.