Because of Eve (1948)

Sally and Bob have been married a year. She might be pregnant, so Dr. West picks up a test sample and tells them to come by in a week for the result. They recall problems they had just before marriage when they found out about each other's past (V.D. and pregnancy). Dr. West had helped them with good counsel and two films ("The Story of V.D." and "The Story of Reproduction"). A week later at his office he has good news and shows them another film, "The Story of Life." Dr. West wants them to know about modern medical science and to teach their kids the facts of life. The movie ends with a commercial for a new five-book-in-one, "The Mid-Century Marriage Guide."