Bundling was the traditional practice of wrapping people together in a bed, usually as a part of courting behavior. The tradition is thought to have originated either in the Netherlands or in the British Isles and later became common in Colonial America. The aim was to allow intimacy without sexual intercourse. Traditionally, participants were adolescents, with a boy staying at the residence of a girl. They were given separate blankets by the girl's parents and expected to talk to one another through the night. The practice was limited to the winter and sometimes the use of a bundling board ensured that no sexual conduct would take place. More often, this rule was merely implicit, and was not always honored. In Colonial America, for instance, 30% of women were pregnant prior to their marriage. What fraction of this was the result of the practice of bundling is unknown.