My understanding was that Margaret Sanger wanted *birth control* (including sterilization) for blacks and other “undesirables” but that she was actually anti-abortion.
It’s true that Sanger was more enforced sterilization than abortion. She disapproved of abortion for the better, Aryan, races but did not oppose it for other, in her view, lesser races. It is no surprise that she was such a hero to Hitler.