ĭespite early inroads of school-based sex education, most of the information on sexual matters in the mid-20th century was obtained informally from friends and the media, and much of this information was deficient or of dubious value, especially during the period following puberty, when curiosity about sexual matters was the most acute. However, in the late 19th century, the progressive education movement led to the introduction of sex education as ' social hygiene' in North American school curricula and the introduction of school-based sex education. Such instruction, as was given, was traditionally left to a child's parents, and often this was put off until just before their marriage. In many cultures, the discussion of all sexual issues has traditionally been considered taboo, and adolescents were not given any information on sexual matters.
