Utah Pull Out 

While having unprotected sex via the "pull out" method, right as the man is about to blow his load and abort mission, the woman wraps her legs around the man, thus locking him in and causing his load to fill inside her. This increases the chance of conception, and therefore a baby. The Utah Pull Out has been very popular in starting large Mormon families, and locking men into marriage after they come home from their missions.

Kathleen used the Utah Pull Out on her brother John so he was locked into starting a large, Mormon family with her. Mormon Utah Pull Out Brigham Young

Utah Pull Out by A Manly Ape May 16, 2016