Sex is never discussed in isolation for its sake or mere pleasure. It is always related to marital life and family life. It is is viewed as a superior human relationship subject to strict regulations. Thus sex within a marital relationship is a worship that is rewarded. Outside a marital relationship sex is a punishable sin.
Sex is a privacy between the spouses.
What goes on is confidential and should not be divulged to outside parties. The human factor in marital and sexual relationship is superior to mere pleasure. Legislation concerning sex is not subject to change by pressure groups or change in social attitudes. Like the rest of Islamic teaching, knowledge about those verses and Traditions on the subject is not age-specific and is not meant to start at a certain age. As the Muslim is leaming the Quran and Sunnah he or she will come across these teachings.