Margaret Sanger did indeed have a lecture at the KKK in New Jersey. But she described it as "One of the most weirdest experiences I had in lecturing" and added that she had to use "the most elementary terms. as though I were trying to make children understand"  She hade a clinic in Harlem with an entirely African-American staff and worked with eminent African-American leaders and professionals who saw a need for birth control in their communities. She received approval from W.E.B. Du Bois who actually served on the board of her clinic and earned praise from Martin Luther King jr.