[3] In 1909, she joined Magnus Hirschfeld in successfully lobbying German parliament from including lesbian women in the law criminalising homosexuality.

In 1921 in Bilthoven, together with Kees Boeke and Wilfred Wellock, she founded an organisation with the name Paco (the Esperanto word for "peace") and later known as War Resisters' International (Internationale der Kriegsdienstgegner, WRI).

The Bund für Mutterschutz sponsored a number of sexual health clinics, which employed both lay and medical personnel, where women and men could go for contraception, marriage advice, and sometimes abortions and sterilisation.

After a papal encyclical, the Casti connubii, issued on 31 December 1930 denounced sex without the intent to procreate,[7] the radical sexual reform movement collaborated with the Socialist and Communist parties to launch one final campaign against paragraph 218, which prohibited abortion.

Stöcker was attending a PEN writers conference in Sweden when war broke out and remained there until the Nazis invaded Norway, at which point she took the Trans-Siberian Railway to Japan and finally ended up in the United States in 1942.