According to a contemporary article in Film Daily, the role of Alan Wythe was originally slated for Melvyn Douglas.
The residence where the wedding took place at the beginning of the film would famously be known two years later as Tara, the O'Hara family home in "Gone With the Wind."
The rivalry portrayed in Man-Proof is ironic particularly because the film studio was using Rosalind Russell as a threat to Myrna Loy. Older and less obviously beautiful than most of the studio's resident stars, Russell had been hired largely to keep Loy in line. Whenever the bigger star balked at a script or demanded more money, executives would simply threaten to give Russell the parts scheduled for Loy. Russell, who lived downhill from Loy, even joked to her about it: "Those scripts. You'd wait until dark, shove 'em out of your house, and they'd roll down the hill and hit my front door, and that's the way they were cast." Loy responded, "Well, you must have been out the night I rolled you Parnell (1937)." (one of Loy's biggest flops) (From Life Is a Banquet by Rosalind Russell).
Man-Proof (1938) marked Myrna Loy's only time at bat with Franchot Tone, who co-starred as a friend who tries to help her get over Pidgeon's marriage to Russell. The film was hardly a happy affair for Tone, however. His marriage to Joan Crawford was breaking up at the time, and he spent many a night sleeping in his dressing room. In addition, he had not scored the quality roles he had hoped for when he first came to Hollywood. Although he had won an Oscar® nomination for Mutiny on the Bounty (1935), by 1938 he was relegated to largely thankless roles that could have been played just as well by contract players Robert Montgomery or Robert Young. He would finish out his studio contract in 1939, then freelance while also focusing on stage work.
The film was a modest success at the box office earning MGM a profit of $217,000 (over $4.66M in 2023) according to studio records.