Since time immemorial, human sexuality has been loaded with multiple meanings: love, pleasure, reproduction, the need for protection and support, the desire to maintain and fortify the bond between man and woman.

To track back the origin of human sexuality, it is necessary to identify human reproductive strategies and these differ substantially in human males and females. Male strategies have been based on two simple mechanisms: ensure continuity of an individual male through the passage of his genes to the largest feasible number of females and select those females who would provide the highest possible quality of oocytes. In contradistinction to this, female strategies have, almost invariably, focussed around the need for protection and support. A human female, has always sought a man capable of providing the best means for her survival and that of their offspring.

In anthropological terms, the sexual behaviour of homo sapiens sapiens evolved from that of the great apes. Given its origin - throughout most of human history - sexual activity has been fundamentally for reproductive purposes. At the same time, in spite of its conceptive origin, human sexuality must have rapidly acquired other meanings, as we occasionally see among big apes and, as non-conceptive sexual activity began to take predominance, external manifestations of an impending ovulation so prevalent in primates (e.g. genital swelling), began to disappear.

A fundamental consequence of non-conceptive sexual activity and the consequent changes that “hid” the appearance of the fertile period, is the need to avoid, rather than seek conception during intercourse and, indeed, n this respect, humans tried to practice contraception ever since they began to leave written records. For millennia however, effective contraception remained a dream; then everything changed during the second part of the XXth century: the availability of modern contraception – enabling humans to separate the meanings of sexuality: to reproduce and to produce pleasure - has represented a true reproductive revolution.

Once started down the road to change, male and female reproductive strategies that had remained unchanged for so long, have now begun a rapid process of never ending evolution. After sex without reproduction, we quickly invented reproduction without sex and this has been followed by reproduction in menopause, although through gamete donation. And, for sure - whether we oppose it or not - human reproductive cloning may be around the corner.

This series of epochal changes have created disconcert, worries and opposition by many. In the final analysis, however, progress should be welcome as long as it does not alter the relationship between parents and children and the biological equilibrium upon which this relationship is built.

In this sense, sexuality is one of the essential bonds for a human couple and studying human sexuality as an integral part of human reproduction will help achieving the respect, protection and promotion of man.