By the time this movie premiered Leslie Caron's husband had divorced her, as she had been in a long term affair with Warren Beatty. Because Beatty had been determined the reason for the divorce, the British court ordered him to pay for all of the court costs.
Warren Beatty only agreed to do this film for the money, which he put toward production of his 1967 masterpiece Bonnie and Clyde (1967).
The film was a Seven Arts production, at the time an independent; so distribution rights were acquired by Paramount. But when Seven Arts merged with Warner Bros., ownership of the film went with it, which is why it airs on TV with a Warner logo.
Caron's baby is named John Thomas. It's unlikely Americans would have known this at the time, but in England, where the film was made, "John Thomas" is a euphemism for "penis."
Rusty's unfinished line "Once I dreamed I went to the opera in my--" was a reference to a then-popular commercial for Maidenform bras.