The author was probably worried that his advice would fall into the wrong hands, because it is full of lots of great "medical" advice like:
"It is particularly dangerous for a girl to start petting with a man the first few times she goes out with him. She should make sure that he is clean, honest and worthwhile. She makes herself cheap by offering easily won kisses. And no man wants a bargain counter wife who has been soiled and manhandled."
In other words, the perfect gift for anyone about to wed.