According to pre-production blurbs in the LA Times, Orson Welles was initial choice to play the title sex researcher (a role that ultimately went to Andrew Duggan), with Janet Leigh and Jayne Mansfield named as two of the female leads.
Warner Brothers filled the film's male roles with Warner Brothers Television contract leads who received no extra money to do the film.
The four women wear the same color outfits throughout the film: the "good" girls, Fonda and Johns, wear white, while the "bad" girls, Bloom and Winters, wear black.
It is significant, and a bit of a private joke, that Glynis Johns reads a specific Dowson poem because it was from that poem that Margaret Mitchell got the title for "Gone With The Wind" and the director of "The Chapman Report," George Cukor, was the director of ...E o Vento Levou (1939) before being fired a few weeks into the shoot by producer David O. Selznick.