Here’s an ad from the July 22 1948 edition of the Toronto Daily Star for a movie to which men and women were admitted separately:
Wikipedia has an entry for Sins Of The Fathers, which was a Canadian film about the effects of syphilis in a small town. The plot synopsis pulls no punches:
Ben Edwards is a crusading doctor who tries to pass a public health law, against the hypocritical opposition of the leaders of the community who profit from prostitution and slums. Finally the opponents find out that they themselves have syphilis and have transmitted it to their own children.
The movie apparently incorporated footage from educational films produced by the U.S. Public Health Service. It was a huge box-office success: Variety reported that there were four-block lineups to get into the Royal Alexandra.
A Google search for Leslie Hamilton, consulting sexologist, turned up nothing.
If you’re curious about the movie, you can download it from the U.S. National Library of Medicine’s digital collections.