The church (some might say cult) I attended in college and where my wife and I got married did not allow any talk of sex until AFTER a couple got married.
They also taught that until you said "I Do," you were to be sexually like a 5 year old. No desires, no opinions, no curiosity, no urges, and no physical responses.
All of that changes magically when "I now pronounce you husband and wife" was said.
They would routinely come around and ask you if you had discussed anything to do with sex and if the answer was yes, they (church leaders) would nullify the engagement and instruct you to never see each other again. If you were unable to do that, they would move one of you to another state, sometimes clear to the other side of the country.