Sexual Education, What Challenges for Tomorrow?

Abstract

In many parts of the world, political and government authorities, school principals, teachers, and parents are not so sure about the need for sex education to young people. They are reluctant to provide it as they dread promoting sexual activity and worse, an unbridled sort of sexuality. Sex education was introduced in schools less than five decades ago, for political and public health reasons. First limited as a whole to “no sex” or “safer sex” and often delivered in an excessively conventional way. More recently, other topics relevant have begun to be added, such as incest, gender identity, sexual orientation, consent relationship, interpersonal violence, and LGBTQIA+. At a time when social networks and online pornography have become young people’s main information sources on sexuality, sexual education is more essential than ever. Clearly, it is high time we had one approach to sex education, serving emotions, the body, human relationships as well as erotic art and ethics. Programs using interactive learning and skill building are essential in engaging young people with the knowledge and tools required for healthy sexual decision-making. Modern implementation strategies of communication, including digital and gaming, are necessary to address young people in a positive way.

1. Introduction

Our approach is consistent with the World Health Organization (WHO) definition of sexuality: “Sexuality is a central aspect of being human throughout life. It encompasses sex, gender identities and roles, sexual orientations, eroticism, pleasure, intimacy and reproduction. Sexuality is experienced and expressed in thoughts, fantasies, desires, beliefs, attitudes, values, behaviors, practices, roles and relationships. While sexuality can include all of these dimensions, not all of them are always experienced or expressed. Sexuality is influenced by the interaction of biological, psychological, social, economic, political, cultural, legal, historical, religious and spiritual factors [1].” This definition highlights that sexuality is part of two distinct spheres: the private, that of the individual, and the public, that of society [2]. Are the boundaries between the private and public spheres so clear-cut?

The role of the public sphere is to promote a state of well-being that addresses the physical, mental, and social dimensions of sexuality and reproduction. It also has the role of promoting sexual health through innovation and sex education, in keeping with human rights, and of developing individuals’ autonomy with due respect for diversity [3]. This public sphere can be liberating for the individual, where gender relations, sexual abuse, and the transmission of sexually transmitted diseases, among others, are at stake [2]. It can also prove restrictive or even oppressive when sexuality education is socioculturally, religiously, or politically dominant, preventing a lasting transition to universal values in relation to sexuality [4]. Even though some prohibitions have been relaxed—thanks to the secularization of society and the retreat, for the most part, of a restrictive sexual morality—the Catholic religion, for example, for a long-time imposed virginity before marriage and the sexual as exclusively aimed at procreating [5]. Today, abortion, which is currently at the center of the American [6] and even French [7] political arena, is a sexual issue over which elections can be won or lost. As for the private sphere, it is theoretically reserved for strict confidentiality and intimacy. Virginity, still cited as an example, is a matter of intimacy and therefore private. However, in a number of societies, the proof of its loss is claimed and needs to be presented to the eyes of all. Moreover, in the age of social networking, some people are exposing their private sphere, as demonstrating intimacy is an issue of value and authenticity in the eyes of peers [2, 8]. In the course of time, boundaries have tended to fluctuate; they have been imprecise and especially complex. This leads to a blurring or even an opposition between the public and private spheres. Therefore, extreme vigilance and permanent foresight are essential to seek a balanced re-negotiation between these two spheres. Sexual health is part of this negotiation. It implies a collective dimension since it deals with common wellness. The challenge is to know how far this approach can be taken without offending deep-seated convictions and without offending individuals’ privacy [2]. Clearly, sexuality education, which is linked to promoting sexual health, is also involved in this ongoing re-negotiation. It is therefore understandable that its implementation regularly comes up against renewed opposition because of disagreements about what should be included in sex education programs [9]. Especially since, in recent years, another view of sexuality such as gender identity, the rejection of heteronormativity, and the LGBTQIA+ movement’s claims are disrupting this already shaky ground. Moreover, in the age of smartphones, texting, Twitter, Instagram, Facebook, and Tiktok, fierce competition confronts public sex education, the media, already being de facto sex educators [10]. Finally, will Artificial Intelligence change our sexuality with the contribution of, among others, erotics (science that deals with the relationship between human beings and robots) and teledildonics, this new connected sex toy industry [11]?

The existing gaps are therefore opportunities for more ambitious and avant-garde strategies. Up-to-date sexuality education based on reliable, scientific, comprehensive information [12], and accessible to all is more essential than ever.

2. The journey of sex education in the west

Concepts of sexuality and sex education are constantly changing between the private and public spheres due to a variety of political, societal, ecological, technological, scientific, ethical, and privacy-related factors. We found it interesting to review, in a necessarily synthetic and humble way, more than 100 years of history, with a view to examining how sex education in schools was born and has evolved over the years in the West. Revisiting the past enables us to see where we stand today and to better anticipate the future. We present the evolution of sexuality education in four periods: 1) before 1900, 2) from 1900 to 1960, 3) from 1960 to 2000, and 4) from 2000 to early 2023. To each period, we add sexuality education vectors, that is, reflections or research results from experts contributing to the advancement of mindsets on sexuality. For greater understanding, we then present the section on the development of sexual health and sexual rights.

2.1 Evolution of sex education

2.1.1 Before 1900: The enlightenment, the first sexual revolution

The eighteenth century, the Age of Enlightenment, was driven by the French philosophical, literary, and intellectual circles and aimed to promote rationalism, individualism, and liberalism against the Catholic Church obscurantism and superstition. It is also called “the Century of Sex” because it initiated the first sexual revolution [13]. This movement for liberating bodies views sexuality as a natural act, which must escape the control of external authorities, including religious. These years were the time when the individual was recognized as an entity and sexuality considered as a private matter [14, 15, 16]. In the following century, arose the idea of a sexuality intrinsically bound to marriage [17].

2.1.2 The period from 1900 to 1960: The awakening and birth of sexuality education

2.1.2.1 Sexuality education

The sexual liberation movement that began in the eighteenth century continued into the twentieth, though not unhindered. Following in the footsteps of the previous century, the early twentieth century was still marked by venereal diseases [18]. Some pioneers began to invest in what appeared to be the beginnings of sexuality education. They included doctors, mainly venereologists, priests hostile to contraceptive practices, freethinkers, and feminists [19]. Sexuality education began to be debated in France as early as 1911 [20]. Pioneers of sexology in the United States included H. Ellis, A. Berge, A. Moll, H. Tavoillot, P. Chambre, S. Freud, W. Reich, and B. Spock. They saw sexuality as an important, if not fundamental, and optimistic component of individual wellness and fulfillment. They emphasized the importance of sexuality education in the process of educating children, adolescents, and adults [21, 22]. For his part, in his December 31, 1929 encyclical “Divini illius Magistri” on education, Pope Pius XI rejected so-called sex education methods [23]. The term “chastity education” was preferred by Church authorities [24]. Despite theoretical and scientific advances [5, 25, 26, 27], for religious, moral, secular, or ideological reasons, the sexuality education that was adopted focused on abstinence and abstinence before marriage. The bonds of marriage were thus made sacred, and sexuality limited to reproduction. Under the guise of “sexuality education,” it had more to do with the pedagogy of chastity and morality. Not only was this omission of education intended to curb the acquisition of knowledge and out-of-wedlock pregnancies, it was also meant to delay the development of feelings and passions [28] regarded as dangerous. The main aim of this no-sex education was to protect the family model and social order, in line with the traditional family model: marry and have children [22]. Although a certain amount of sexuality education did exist, responsibility for it lied mainly with the family, with parents, and to a lesser extent with religion, in the form of prohibitions. Table 1 summarizes the characteristics of this approach, which we call Approach 1.

Times	Approaches	Values	Objectives	Content being taught	Themes	Spheres of learning
<1900	1; Pedagogy of chastity; and morality	Chastity; Virginity; Sacredness of the marriage bond where sexuality is limited to reproduction	To prohibit: sex relations To postpone: sex in marriage To ward off: out of wedlock pregnancies	No sex; Abstinence Abstinence before marriage	Mainly prohibitions For some: anatomy and physiology of the human body	Family sphere; Religious sphere
<1960	2; Medical pedagogy; Listing of health problems that may have negative effects; Good health; Sexual health	Sexual and reproductive; health; Political and moral legitimacy of non-reproductive sex; Good health and sex health	To prevent: STIs/HIV unwanted pregnancies To improve: Sexual life Sex relations	No sex and Safer sex; AOUM Abstinence as an option + contraceptive methods; + Safer sex; Emotional and relative life	Anatomy and physiology of the human body (Biology courses) Emotional and relative life	Family sphere Religious sphere School sphere, recommended and then mandatory Family planning International sphere
<2018	3; Secular pedagogy; citizen, egalitarian and non-discriminatory based on a factual approach	Human and sexual rights; Social and egalitarian dimension Sexual and reproductive health Positive sexuality Autonomy Openness to pleasure Respect for the person’s health Well-being and dignity	To prevent: inequality sexual violence sexual abuse STIs / HIV Unwanted pregnancies cyber-bullying To adopt: inclusion respect equality empathy responsibility reciprocity	Comprehensive sexuality; education; CSE; Themes with learning objectives: knowledge attitudes skills Age and developmentally appropriate parts: 5–8 years old 9–12 years old 12–15 years old 15–18 years old and over	Key concept 1: Relationships; Key concept 2: Values, Rights, Culture and Sexuality; Key concept 3: Understanding Gender; Key concept 4: Violence and Staying Safe; Key concept 5: Skills for Health and Well-being; Key concept 6: The Human Body and Development; Key concept 7: Sexuality and Sexual Behavior; Key concept 8: Sexual and Reproductive Health	Family sphere School sphere mandatory Family planning International sphere Non-formal and community settings: Sports centers; Faith-based organizations Professional networks; Youth movements; Health institutions; School holidays; Online platforms
<2023	4; Secular and hedonistic pedagogy; citizen, egalitarian and non-discriminatory based on a factual approach	Positive and hedonistic; sexuality; Human and sexual rights Social and egalitarian dimension Sexual and reproductive health Self-awareness Self-confidence Awareness of the other Sharing and reciprocity Self-reliance Respect for the individual’s health Well-being and dignity	To prevent: inequality sexual violence sexual abuse STIs / HIV unwanted pregnancies cyber-bullying To adopt: inclusion respect equality empathy responsibility sharing and reciprocity To fell and become: fulfilled and happy competent in one’s situation by assuming one’s personality	Comprehensive sexuality and self-confidence education; CSSCE; Thematic with learning objectives: knowledge attitudes skills Age and developmentally appropriate parts: 3–18 years old and over for Basic Key concept 5–8 years old 9–12 years old 15–18 years old and over with contribution of neuro, emotional and sexual sciences	Basic Key concept: Intrapersonal relationships; Key concept 1: Relationships; Key concept 2: Values, Rights, Culture and Sexuality; Key concept 3: Understanding Gender; Key concept 4: Violence and Staying Safe; Key concept 5: Skills for Health and Well-being; Key concept 6: The Human Body and Development; Key concept 7: Sexuality and Sexual Behavior; Key concept 8: Sexual and Reproductive Health	Family sphere School sphere mandatory Family planning International sphere Non-formal and community settings: Sports centers; Faith-based organizations Professional networks; Youth movements; Health institutions; School holidays; Online platforms; Peer networks Training centers public and private Media, AI, etc. With quality labels

Table 1.

Approaches to sex education.

2.1.2.2 Vectors of sex education

The sexuality education pioneers’ work fortunately opened up a breach in the protectionist and moral fortress of no sex and sexuality for the sole purpose of procreation [29]. This breach was widened by the first scientific studies on sexuality, such as those by Kinsey. His 1948 and 1953 publications challenged the strict opposition between homosexuality and heterosexuality. The idea that heterosexual orientation, unique and pure, would be different from homosexuality collapsed [30, 31]. The outcome was a major step forward in the recognition of homosexuality.

In addition, three women questioned the stereotypes associated with femininity and introduced an early way of conceptualizing gender: Viola Klein, an Austrian-born specialist in women’s social policies in the post-war welfare state (1944). She introduced staunch conceptions of equality and freedom [32]. In 1949, French philosopher Simone de Beauvoir published “Le deuxième sexe.” She advocated “equality in difference” and women’s emancipation [33]. As for Margaret Mead, an American cultural anthropologist, she was responsible for the first reflection on sex roles in the 1930s. Based on her anthropological observations, she came to regard the assignment of certain character traits to men or women as arbitrary [34, 35, 36, 37].

2.1.3 1960 To 2000: Sexual education, recommended and then compulsory, the second sexual revolution, the beginnings of sexual health

2.1.3.1 Sexuality education

Whether in the United States, Canada, or Europe, efforts to have sex education recognized as a collective right began around 1960–1970. Structured and official sexuality education was henceforth seen as essential. This idea was promoted, among others, by the American sexologists Masters & Johnson (1966–1970), by the legalization of the contraceptive pill (1967), by the May 1968 events and by the liberalization of abortion (1975). One thing is for sure: sexuality changed in status, there was a dissociation between sexual activity and procreation [30]. This association, namely “effective contraception” and “discovery of orgasm,” thus gave rise to the contraceptive revolution; the second sexual revolution took place. Sexuality with erotic purpose became a legitimate object of knowledge, and it also legitimized for each one to express their sexuality [6, 29, 38]. These societal advances led to the introduction of the first sex education programs. These were designed to awaken responsibility while remaining largely evasive about sexuality itself [39]. Although the family and religious spheres retained all their influence, sexuality education in schools was optional and then became compulsory in 1975. The introduction of emotional and relational life was initiated to a greater extent in Europe than in the United States [40]. During that period, three distinct and complementary teaching contents can be identified:

∙ Abstinence Only Until Marriage—AOUM: This pedagogy mixes moral aspects with medical purposes, centered on the prevention of sexual problems likely to have repercussions on health such as teenage pregnancies and STIs. While affective aspects were introduced, they were framed within the narrow confines of the family and procreation. Discourse was based primarily on the argument of psychosexual immaturity: the body was physically mature, but it was deemed socially immature to enter into a lasting love relationship. The essential message during this period was therefore to have sex as tardily as possible [40]. In general, there was no explicit encouragement to have an active sexual life, especially regarding girls [29]. The information must be scientific, and it naturally found its way into school biology classes.

∙ Sexual health: this concept was introduced in 1975 by the WHO [41]. Although the relevance of sexual education was accepted, it was problem-solving-oriented with a rather defensive perspective. In continuity with the definition of health that it had established 27 years earlier, the WHO was committed, on the other hand, to the consecration of sexual optimism. It promoted the concept that sexuality contributes “to better health and wellness when it can be experienced and practiced freely, without constraints, but certainly not without specific rules” [42]. Moreover, the WHO engaged in the process of legitimizing the dissociation between reproductive and non-reproductive sexual activity [29]. Sexual health was defined as follows: “the integration of the somatic, emotional, intellectual and social aspects of sexual well-being in that they can enrich and develop personality, communication and love. The concept of sexual health involves a positive approach to human sexuality. The goal of sexual health is the enhancement of personal life and relationships, not just counseling and care for reproduction or STDs.” [41]. The concept of sexual health thus broke away from venereology and gynecology to focus on wellness and the medicalization of wellness [42]. Within this framework, it also developed the nomenclature of health problems that can have negative effects on sexual health and sexuality.

∙ Safer sex: This approach was characterized by the arrival of the early 1980s AIDS epidemic. In the absence of an effective treatment, sexuality education, which in the 1970s had taken on the trappings of a more libertarian ideological struggle, became essentially a public health tool, without however completely ignoring moral aspects. The notion of risk-free sex, also called Safe sex or Safer sex, was introduced in the curricula. It was added to the information already provided on contraception and included a set of practices intended to reduce the probability of passing on STIs, such as HIV. Messages focused on condoms [43], which became the ritual for entering sexuality. Sexuality education was then more oriented toward the prevention of STIs to the detriment of real sexual and emotional education policies [44]. In those years, sex education was still too limited to the prevention of sexuality as a risk of death or unwanted life [45]. This medical pedagogy leads us to Approach 2 (Table 1).

2.1.3.2 Vectors of sexual education

Several research works are worth mentioning. In 1972, the British sociologist and feminist Ann Oakley published a book, “Sex, Gender and Society,” where she differentiated between anatomical sexual differences (sex, which would be invariant) and social differences (gender). She thus further advanced the concept of gender in the public mind [46]. In 1976, Shere Hite published her “Hite Report” in the United States, presenting the results of her survey on female sexuality. It showed that most women often reach orgasm alone through masturbatory practices, but that they remain mostly dissatisfied when having intimate relationships with their male partners [30]. The feminist movement emerged strengthened. Michel Foucault, a philosopher of the history of sexuality, took a stance in 1976, with the publication of his first volume on “The Will to Know.” He explains the ineffectiveness of standing up against a repression of sexuality in order to liberate it. He shows rather how sexual life has triggered a systematic urge to know everything about sex, which has been systematized into a “science of sexuality” [47]. In 1989, the African-American jurist Kimberlé Williams Crenshaw introduced the concept of “Intersectionality” [48, 49]. She presents the notion of the accumulation of several social handicaps. This jurist helps to understand how black women (first handicap) or poor women (second handicap) do not suffer the same violence or discrimination as women from privileged and white socio-professional classes [50]. She strengthened the feminist movement and also contributed to the development of the gender movement. In the same vein, American sociologist Judith Butler published her book “Trouble in Gender” in 1990. She believes there are as many genders as there are individuals, so kiss goodbye to the masculine on one side and the feminine on the other. She atomizes the idea that there are only two genders. It also lays the foundations of “Queer Feminism,” a feminism that thinks outside the opposition between the two genders and considers that neither the gender nor the body are binary [48, 51].

2.1.4 Between 2000 and 2023: Sex education, sexual health, and sexual rights as a coherent whole

2.1.4.1 Sex education

Recommendations for sexuality education prior to the 2000s were gradually bearing fruit. More and more countries were making sex education compulsory both in primary schools and in junior and senior high schools, for example in France, at the rate of three sessions per year. Some governments, in collaboration with universities, agencies, and associations, have been investing in updating and distributing their guides for school principals and teachers [52, 53, 54, 55, 56]. With these reference documents, schools were provided more guidance on what to teach. However, there was still not enough exchange among countries to develop common sexuality education strategies and programs. This also made it difficult to evaluate the impact of sex education [40].

The first international frameworks for sex education were developed as a result of numerous meetings and work among experts in sexual health and education. These initiatives were supported by the WHO, the United Nations Educational, Scientific and Cultural Organization (UNESCO), Joint United Nations Program on AIDS (UNAIDS), the United Nations Population Fund (UNFPA), and the United Nations Children’s Fund (UNICEF) between 2001 and 2009 [40, 57, 58, 59, 60, 61, 62]. In 2010, WHO published the first version of its “Standards for Sexuality Education in Europe” [40]. At the same time, UNESCO, in collaboration with other organizations, published the first version of the “International Technical Guidance on Sexuality Education” [63]. These two reports share some similarities. They serve as frameworks for policy-makers and authorities responsible for sexuality education. With the publication of these frameworks, many countries further improved their sexuality education programs.

Following the major advances in gender equality, the fight against violence against women, and the inclusion of LGBTQIA+ and gender concepts (see 2.2.), it has become essential to integrate these concepts into the new sexuality education programs. A revised version was therefore necessary. Hence, UNESCO, together with UNAIDS, UNFPA, UNICEF, UN Women and WHO, published the second version of the “International Technical Guidance on Sexual Health” [64]. This approach intended to go beyond previous sexual education programs and focused on abstinence, problems, and their prevention. For this reason, it has been called “Comprehensive Sexuality Education” (CSE). In addition to lessons on the human body and its sexual development, fertility, contraception, sexuality and STI prevention, concepts related to sexual rights, psycho-affective development, consent, respect for and inclusion of sexual minorities and gender differences were added, all based on a factual approach that was intended to be secular, civic-minded, egalitarian, and nondiscriminatory. We have called it Approach 3. (Table 1) CSE is defined as “a curriculum-based teaching and learning process that addresses the cognitive, affective, physical and social aspects of sexuality. It aims to equip children and youth with the knowledge, skills, attitudes and values that will enable them to develop their health, well-being and dignity; to develop respectful social and sexual relationships; to explore the impact of their choices on their own and others’ well-being; and finally, to understand and defend their rights throughout their lives.” The guiding principles are organized around eight key concepts of equal importance. They are mutually reinforcing and meant to be taught together. These key concepts are divided into two to five themes (27 concepts in total) (Figure 1). Each theme is tentatively broken down into key learning objectives to help guide the development of locally relevant curricula. The learning objectives are age-appropriate and follow a logical sequence (i.e., they become more complex as youth age and mature) based on four age groups: 5–8 years, 9–12 years, 12–15 years, and 15–18 years and older. These principles are voluntary, not mandatory, and are based on current knowledge and international good practice. They take into account the diversity of national contexts sexuality education is provided in. These guidelines have far-reaching implications for advancing global development agendas and for addressing adolescents’ health and well-being worldwide [65].

Figure 1.

Comprehensive sexuality and self confidence education—Approach 4.

2.1.4.2 Vectors of sexuality education

In 1998, 30 years after the discovery of the moon, Australian urologist H.E. O’Connel presented the complete anatomy of the clitoris. Previously, only the glans and the cap were known, since they were visible to the naked eye [66]. Her work was then relayed in 2016 by Odile Buisson, an obstetrician gynecologist and Dr. Pierre Foldès, a pioneer of clitoris excision repair. The latter highlighted the clitoris is of no use for procreation but is actually an organ for sexual enjoyment [67]. To disseminate this breakthrough, Odile Fillod, a specialist in popularization, created the three-dimensional clitoris, also called the bulbo-clitoral organ [68]. For the first time, in 2017, a complete representation of the organ was illustrated in the “Life and Earth Sciences” textbook [69]. The clitoris became popular, and it was no longer reserved to a handful of scientists, feminists, or lesbians. This discovery, easily represented in monochrome plastic version, had a huge impact in the media and networks. M. Mazaurette and D. Mascret entitled their book “The revenge of the clitoris,” thereby showing how the female sex had been gagged over the centuries and sometimes even with women’s support [70]. On the subject of the clitoris, A. Koechlin claimed the production of knowledge, just like the production of ignorance, were eminently political issues [71].

2.2 The development of sexuality education and sexual rights, involvement in sexuality education

On many occasions, sexuality education content is undeniably part of a permanent negotiation between the private and public spheres. In the public sphere—despite numerous social, political and cultural obstacles—the successive and painstaking investment of international intergovernmental and nongovernmental organizations, as well as members of the World Association for Sexual Health (WAS), greatly influenced the way sexuality education was conceptualized, along with the content of the programs designed to implement it. The resulting actions have enriched sexuality education by introducing the concept of sexual health and integrating the concept of sexual rights into the human rights framework. In the following, we chart the progress made in this area over the past 60 years. Figure 2, inspired by A. Giami’s articles on this subject, summarizes the development of sexual health and sexual and human rights stages that have influenced the content of sexuality education programs.

Figure 2.

The development of sexual health and sexual rights, involvement in sex education.

In the 60s, the first steps toward opening up human rights to sexual, reproductive, and gender issues were taken. In 1968, representatives of 120 countries took part in the first International Conference on Human Rights, organized by the United Nations [72]. The ensuing so-called “Teheran Declaration” introduced an indirect reference to sexuality as part of the field of human rights, through family planning and the denunciation of social discrimination and violence against women. Initially, sexuality education was limited mainly to premarital sexual abstinence as well as the prevention of STIs and pregnancies outside marriage. The initiative came in response to the need for solutions to these problems. In 1975, WHO shifted its focus to the reasons why engage in sexuality education. This more unifying and meaningful strategy integrated sexuality education into a higher dimension of sexual health [41] (defined above). With this landmark decision, the WHO endorsed “The principle of the association between non-reproductive sexuality, well-being and personal fulfillment” [29]. This work was of vital importance to the advancement of sexuality education at international level. This approach was further extended by the WHO in 1987. From then on, the international organization now has encompassed, within sexual health, concepts such as education, information, counseling, and sex therapy. The need to improve professional training and research was also determinedly reaffirmed. In addition, the WHO now takes account of the public health dimension and political issues linked to human rights, affirming “the rights of individuals to be free from sexual exploitation, oppression and abuse.” Sexual health is therefore associated with rights, as well as a state of wellness [73]. The drive to include sexual and reproductive health, as well as gender, in the field of human rights has since experienced numerous international developments. From 1993 to 1995, a succession of world meetings were held on human rights (Vienna Declaration) [74], population and development (Cairo) [75], and women (Beijing) [76]. They focused on violence against women, the freedom to lead a satisfying and safe sex life, the abandonment of exclusive reference to family planning, women’s right to control their sexuality, and gender equality. This work constituted the matrix of the first wave of human rights applied to sexuality. Mobilization in favor of sexual rights had undeniably begun. These include the “Charter on Sexual and Reproductive Rights” by the International Planned Parenthood Federation (IPPF) in 1996 [77] and the first WAS “Declaration of sexual rights,” in Valencia in 1997 and Hong Kong in 1999 [78]. In 2000, the Pan American Health Organization (PAHO) and WHO, in collaboration with WAS, updated the concept of sexual health. These three international organizations consolidated the hybridization of the notions of sexual health and sexual rights. Without the provision of sexual rights, they consider the objectives of sexual health cannot be achieved and maintained [79]. As health protection is a fundamental human right, it then follows that sexual health is based on sexual rights. This deduction has become increasingly obvious, so much so that the association between sexual health and sexual rights has become the “regime of truth” for sexuality, mainly in the Western world [79]. Two years later, in 2002, the WHO issued its “Definition of sexual health and sexual rights in the context of reproductive health” [80]. This declaration integrates the dimension of consent, i.e., the right to have coercion-free sexual relations, which primarily concerns the rights of women and children. The declaration also places greater emphasis on erotic sex life than on reproductive health. In addition, the WHO opens up a public health perspective by emphasizing access to care and services as well as sex education [81]. The journey toward the inclusion of sexual and reproductive health in the field of human rights continued and reached a new milestone. In 2005, at its 17th sexology congress in Montreal, the WAS presented the “Montreal Declaration, Sexual Health for the Millennium.” This declaration includes eight rights in all but puts sexual rights at the top of the list and brings sexual health and recognition of sexual pleasure’s health benefits back to the debate center stage [81, 82]. For its part, IPPF presented its second version on sexual rights, the Revised Charter on Sexual and Reproductive Rights (in 2008). This declaration focuses primarily on reproductive health, women’s health, and the right to family planning in the best access conditions, as well as the right to equality in the face of all forms of discrimination [79, 82]. Parallel to these advances, issues related to gender identity, homosexuality, and the fight against discrimination are also emerging. There were also a number of landmark pronouncements on these issues, which had an impact on the content of sexuality education syllabuses. A case in point is the international meeting held in Indonesia in 2007, which resulted in the “Yogikarta Principles” for International Human Rights Law on Sexual Orientation and Gender Identity. This document is essential for LGBTQIA+ representatives, as it confers them strict equal rights. It also initiates the fight against the discrimination these people are subjected to when it comes to their basic civil rights [79]. In the same vein, the “European Commission’s report on human rights and gender identity” was published in 2009. This document sets out a series of recommendations to protect transgender people’s human and sexual rights. The report mentions, among other things, the recognition of hormonal and surgical treatments and psychological support, shortening the duration of civil status change procedures, abandoning definitive sterilization to change sex [79, 83].

Four subsequent events reinforced the notion of sexual rights, which had become a compelling theme [73]. In 2014, the WAS, the first to take a stand, presented a new “Declaration of Sexual Rights,” following on from its 1997 declaration [84]. It was followed in 2015 by the WHO, which published a broad document on “Sexual health, human rights and Law” [85]. Also in 2015, the United States Government publicly recognized the importance of sexual and reproductive health and rights, with the term sexual rights now being used “Sexual and reproductive health and rights” [73]. Finally, in 2010, UNESCO instituted a Chair in “Sexual Health and Human Rights.” One of its main activities is to develop health professionals’ teaching and training in the field of sexual health and human rights [73]. These four events were converging toward the institutionalization of sexual rights. Sexual health and sexual rights are not therefore a normative category that is imposed “by right” [86]. In fact, this institutionalization is the result of a long process that began in 1968 and has been driven by the successive adoption of firm, or less firm, decisions by international organizations [73]. However, such institutionalization is not the end of the story, since sexual rights are constantly evolving. One example is the “Declaration of Sexual Pleasure” published in 2021 by the WAS [87]. In it, sexual activity is recognized as a source of pleasure and therefore of health. Sexuality for erotic purposes thus becomes a legitimate object of knowledge [38].

This brief historical overview explores the key stages in the development of sexuality, sexual health, and sexual rights [88]. However, a number of important issues do linger despite these undeniable advances [81]. Some organizations prefer to focus on reproductive health rather than sexual health. As a result, sexual rights cannot yet be differentiated from the field of reproductive health [81]. Furthermore, the current proliferation of nonreproductive recreational sexual relations, including masturbation and homosexuality, as well as the generalization of relationships outside marriage, pave the way for the promotion of consensual sexual relations. They also highlight the battle—still to be waged—against the sexual constraints too often exerted on women [81]. Another factor is that the texts instituting sexual rights too often betray essentially heteronormative agendas [81]. Opening up sexual rights to trans- and more generally to LGBTQIA+ people is still a matter of debate due to the discrimination and violence directed at these communities because of their identity characteristics [79]. As for gender-related issues, we wonder how far this will lead to, given the emergence of gender diversity and fluidity, implying a profound change in mentality linked to the right to self-defining identities [79]. Following this path, we now understand the reasons why CSE programs are enriched by the integration of sexual health and sexual rights, even though not all the recommendations are yet to be operationalized in the field.

3. Analysis of approaches to sexuality education

3.1 What does the literature review tell us?

Recent studies of the literature, mainly in the form of systematic reviews, have been carried out to ascertain the impact of sex education approaches and the factors fostering their integration [89, 90, 91, 92, 93]. This work lends us the opportunity to summarize what is working, what does not, what’s missing, what needs improving, and what questions are still outstanding. They open the way to new proposals to enrich the current approach to CSE Approach 3 [64].

3.2 What is working?

There are many arguments in favor of CSE Approach 3 [64]. It emphasizes the positive aspects of sexual and reproductive health [90]; it does not lead to an increase in sexual activity, risk behaviors, or STIs/HIV infection rates [64]. On the other hand, it can lead to a delay in initial sexual intercourse or encourage the use of protection or contraception on first having intercourse [90, 91]. What’s more, it acts at different levels: it goes beyond risk behaviors. It also improves knowledge and skills by promoting healthy relationships; it strengthens child sexual abuse prevention skills and reduces intimate partner violence; it improves understanding of gender and gender norms and reduces homophobia and homophobia-related bullying [89]. Furthermore, the literature shows both the effectiveness and importance of addressing gender and sexual orientation in the contexts of human rights and legality [89, 90].

3.3 What does not work?

According to an overwhelming majority of studies, sex education programs based on AOUM Approach 1 fail to delay entry into sexual life, nor do they prevent risky behavior [94, 95, 96]. Young people say they do not receive—from their parents or other legitimate sources—the basics for positive, respectful sexuality, and sexual relationships [97]. As for educators, their training does not adequately prepare them for their multifaceted role, especially as sexuality differs from other subjects [39, 98, 99]. What’s more, teachers are not always comfortable talking to young people about sexuality and gender [64]. Some feel they lack knowledge, skills, confidence, and ease when talking about sexuality [92].

3.4 What’s missing?

The absence of a relational context is predictive of poor school results [89]. Young people feel ill prepared for healthy [100, 101], romantic, loving, and lasting relationships, especially by parents, teachers, and other adults, which leads to anxiety [92]. The vast majority of parents are silent on topics such as misogyny, sexual harassment, consent, and interpersonal violence or gender issues [92]. The same applies to the high rates of sexual assault among young people [92]. The implementation of human rights and gender equality is very poor [102]. The collective heteronormative heritage marginalizes LGBTQIA+ people and hinders the development of healthy relationships [103]. Abortion and genital mutilation are also rarely addressed [102].

The themes of pleasure and desire are currently excluded and do not meet young people’s needs, especially as educators are often uncomfortable addressing these subjects [6, 89, 90]. There is as yet no real consensus on the criteria for defining sexual well-being and other aspects of positive sexuality [104]. Twenty-three articles reveal significant gaps in erotic education, gender equity, vulnerability, connection, communication [93], and knowledge, in particular, about first sex [93, 105]. Key components identified as an optimal sexual experience include presence; connection accompanied with sharing and reciprocity; deep sexual and erotic intimacy; authentic communication; risk-taking and interpersonal exploration; authenticity; vulnerability and transcendence [93]. This development of erotic skills is therefore emphatically encouraged [93]. In terms of form, what is lacking is a playful pedagogy that makes it easier to open up dialog [92].

3.5 What needs improving?

Start CSE early, even from kindergarten onward, and well before sexual activity begins. This early approach helps prevent sexual abuse and provides self-protection [89, 106]. In addition, it is highly advisable to organize long-term, staggered education that is age-appropriate and disregards gender and sexual orientation stereotypes [89].

In terms of themes for improvement, young people are asking for psychological and emotional skills to cultivate healthy relationships that pave the way for safe and enjoyable sexual experiences, whether in friendship, one-night stands or romantic relationships, all of which are essential for optimal health and well-being [9, 89, 90, 92, 93]. Knowing how to deal with difficult emotions can also help youths improve their academic performance [9, 89]. CSE Approach 3 fortunately addresses sexual health beyond the biological aspects of sex [90]. When pleasure and desire are addressed, pleasure is too often associated with “danger pleasure,” whereas the need for information is based on “satisfaction pleasure,” without falling into the “pleasure imperative” trap [107, 108, 109]. As for desire, it is a subject that deserves a great deal of thought, especially for women, on account of this: Is desire focused on pleasing the other person, or on expressing one’s own desires [110]? Young people are also asking questions about how to communicate and better satisfy their partner(s) [111]. What’s more, healthy sexuality that is all about pleasure and intimacy makes people want to have sex [93]. Moreover, addressing the issue of gender and power [112] can multiply the effectiveness of risk behavior prevention. This subject is of less interest to men but is inherent to gender inequalities [113]. The younger generation is also calling for more inclusive sex education for LGBTQIA+ people, irrespective of sexual orientations [92, 114, 115]. They call for the struggling against homophobia and transphobia [9]. A hostile environment is associated with poorer school results. Conversely, a favorable environment promotes success and improves mental health. Integrating themes such as intersectionality, sexual orientation, and origin, class and culture considerations into the “Social justice” dimension also meets a demand [89]. LGBTQIA+ people are also demanding dialog on the subject of healthy relationships, sexual orientation, gender identity, sexual pleasure, and communication [92]. As for queer and trans youths, they need sexuality education that is relevant to their lives [9, 92]. Young people also want more debate on sexual health issues across a broad educational spectrum [92]. One request remains important: to extend CSE to people with disabilities. These poor relations of sexual education are, in fact, more exposed to sexual health risks, sexual abuse and exploitation, unwanted pregnancies, and STIs [89].

As far as teachers are concerned, young people say they need qualified educators to talk about sexuality at ease and with preparation [92]. To achieve this, teachers need to understand their own values, assumptions, and experiences where their own sexuality is concerned [92]. Young people want educators who are confident [116], who encourage them to stimulate reflection, develop empathy and critical thinking, and who look at sexuality in a positive and inclusive way [92]. Teachers who address homophobia, transphobia, and other issues specific to LGBTQIA+ youths need specific training [92]. All this requires adequate financial resources and practical support [92]. Young people are also very interested in peer teaching with expert support [115, 117]. They listen to peer educators, opinion leaders, and influencers, even though these approaches still leave room for improvement [115].

As far as the teaching itself is concerned, teaching methods should be more playful and therefore more attractive. Board games, card games, ice-breaking exercises, activities that get people moving, quizzes, multiple-choice questions, fun approaches, and jokes are all desirable, as they open the door to debate and dialog with teacher and peers alike [92]. Counseling young people by working on emotions, for example, with the help of artificial intelligence, as proposed by UNESCO with the Sacha system [117], is also very promising.

As for schools, A.J. LaVanavay questions the appropriateness of the school as a place for teaching sexuality. In any case, she questions its role in this respect [9]. On the other hand, S. Denford et al. believe that schools play a key role in the implementation of sex education [118]. At school, it is important to include the subject in other courses too, such as social studies, languages, physical education, mathematics, music, and art [89]. Today’s teenagers are influenced by the digital and technological environment. It is hence all the more important to tailor sexuality education interventions to this environment. Online searches for information on everyday health issues, sexual health, and physical well-being are on the increase [119, 120, 121]. B.J. Gray et al. consider the Internet to be an increasingly important source of information and advice on this subject for young people and adolescents [122]. Also, many authors advocate digital platforms and blended learning (school and Internet) as promising greater effectiveness in promoting teen-age sexual health [123]. In addition, a combination of face-to-face and digital interventions seems preferable, given the Covid experience [124]. Access to information is facilitated by smartphone applications, which are becoming an increasingly important vehicle for sexuality education [124]. Thanks to their ubiquity and popularity, digital media offer a promising avenue for sex education, especially as the confidentiality and anonymity they provide suit young people [125]. In the school environment—both inside and outside the classroom—digital interventions offer greater flexibility than traditional face-to-face interventions when it comes to a variety of learning needs and benefits. This lower-cost medium also brings numerous possibilities for personalization, interactivity and a safe, controlled and familiar environment for the transmission of sexual health knowledge and skills [125, 126, 127]. At the same time, rigorous evaluation is required, particularly with regard to the opportunities offered by new technologies, which can lead to more cost-effective interventions than face-to-face programs. In view of their relevance, these new technologies are therefore highly recommended [89, 90, 128]. The same applies to peer-led digital programs [128].

3.6 Unanswered questions

Over the past generation, the Internet has introduced a new professional, social, personal, and sexual way of life [129]. Interpersonal relationships are becoming more distant, through our screens and connected objects, right down to the most intimate aspects of our private lives [129]. Today, spurred on by the isolation imposed by the Covid-19 pandemic, the arrival of digital technology and the world of tech, or shall we say “sextech,” have accelerated the opening up to other modes of enjoyment. Their aim is to combine the quest for sexual wellness with technological innovation. This new way of functioning includes the connected objects we already know about, but also robotics, virtual reality, artificial intelligence, immersive technologies, to name a few [130]. New intimate scripts are being developed through the practice of cybersexuality, pornography, and the use of sex toys. The path to assisted orgasm is now also more accessible to the sexually excluded the disabled and the elderly. Erobotics, which brings together humans and robots, is growing fast. Today, these new sexualities are spawning more questions than answers, and it is time we got to grips with them as soon as possible.

3.7 The metaphor of learning how to drive a car

Approaches 1 and 2 to sex education are conservative, protective, and even restrictive. They are not effective, preventing neither unwanted pregnancy nor STI/HIV. What’s more, they fail to meet young people’s needs and demands. While Approach 3 has the merit of gaining consensus internationally and among young people, it is not yet applied for all in an optimal way, and its implementation requires a great deal of adaptation, depending on the country and the existing culture. Young people report they are not sufficiently prepared to establish an intimate and fulfilling relationship with another person, whether lasting or short-lived [131].

The metaphor of learning to drive a car illustrates these approaches state of affairs. The first approach is not to bother to drive. This removes any dread of danger, but then of course it deprives you of the opportunity to travel in this mode. The second is to focus totally on the risks of accidents resulting from one’s own or others’ carelessness. This is the safety approach. The third approach is to learn the rules of the road as a good citizen: respecting priorities, speed, the meaning of traffic lights, road markings, communicating with others, headlights, indicators, horns and what have you; respect heavy goods vehicles, two-wheelers, and pedestrians. While these notions are essential to integrate, the journey is still at deadlocked. At this stage, aspiring drivers remain on the sidelines. In the meantime, they observe drivers taking part in the “Goodwood Festival of Speed,” a paradise for car enthusiasts and speed lovers. He therefore believes that driving means opting for maximum speed and force (#porno) and acts similarly if no other information is provided. He’s missing the fourth way. It means learning to drive in real, not virtual, conditions, alone or accompanied, in the countryside, in traffic jams, on the freeway, in the mountains, knowing your rights and those of others, confidently mastering the brake and gas pedal at slow, moderate or fast speeds. It means being equipped to take on the dream and enjoy the escape.

4. Proposal for a fourth approach to sex education

CSE Approach 3 therefore deserves to be enriched at various levels, as implicit needs and demands remain to be met. It is therefore important to create and reinforce these themes, to better prepare teachers, to innovate and diversify the places and means of transmitting information, and to foster access to it for all. Let us be more explicit about themes.

CSE proposes nine keys (Figure 1) broken down into 29 themes. We have added a new key, the basic one: intrapersonal relationships. After all, how can we position ourselves in terms of consent and deal with unwanted pregnancies, violence, discrimination, gender equality, romantic relationships, and decision-making without having learned and assimilated solid emotional baggage such as self-awareness and self-confidence? That is why we have added this dimension. Emotional competence is the ability to identify emotions, understand what triggers them, express them, and regulate them [132]. Moreover, the acquisition of such competence is predictive of good physical and mental health [133] and has a significant impact on psychological, social, and physical adaptation [134, 135, 136, 137, 138, 139]. Current research highlights the need to develop this emotional competence at school [133]. We consider it essential and a priority, since it serves as a pillar for all the other keys and for the healthy fashioning of one’s own life [140, 141]. That is why we propose it be developed as early on as kindergarten. To our knowledge, some sex education guides are beginning to introduce that dimension explicitly [142]. UNESCO also attaches importance to the notion of counseling [117]. However, this is far from sufficient. Under Key 4: Violence and security, in line with the literature review, we have added female genital mutilation (excision) to Theme 4. This practice, which is a violation of human rights, still exists in 31 countries [143]. Of the 27 themes developed in the 8 keys, the poor relation is key concept n°7, sexuality and sexual behavior. Only two themes are developed: Theme 1 concerns sex, sexuality and the sexual life cycle, and Theme 7.2 deals with sexual behavior and sexual response. The points raised concern fantasies, masturbation, condom use, and the complexity of sexuality. It’s true the WAS charter on the right to pleasure wasn’t published until 2021 [87], which may explain why pleasure is not yet clearly mentioned. However, in view of the analysis of the literature corresponding to the lack of knowledge, notion of pleasure and desire as well as erotic skills, we add three other aspects: 7.3. Orgasm and its triggers, both female [144, 145] and male [129, 146, 147]. 7.4. Pleasure and desire. And 7.5. erotic skills, to increase sexual confidence. Figure 1 presents the keys and themes of approaches 3 and 4. We thus propose Approach 4: comprehensive education for sexuality and self-confidence CESSC, based on UNESCO’s International Guidelines on Sexuality Education. This fourth approach is hedonistic, secular, civic-minded, egalitarian, and nondiscriminatory, grounded in a fact-based approach. Table 1 explains this approach in greater detail.

To quote V. Boydell et al., “We are aware the inclusion of pleasure in sex education is an ideal or model yet to be achieved, as there are political, social and moral barriers to such inclusion. However, pilot studies or further research into the benefits of erotic education could highlight not only sexual benefits, but also relational and psychological benefits” [148].

5. Sex education: What challenges in future?

Despite 2 years of confinement and loss of bearings due to Covid-19, we are experiencing an “acceleration of history” [149]. There is an overabundance of events and information that are gathering speed. In the early twentieth century, marriage-related sexuality was limited to reproduction. The 60s sexual revolution and the emergence of sexual health helped legitimize nonreproductive relationships (masturbation and homosexuality) and relationships outside marriage. In the twenty-first century, attention is focused on a type of sexuality linked to consent, in reaction to the constraints placed mainly on women and children; a rejection of heterosexuality as the sole reference point; a fight against discrimination linked to sexual orientation and gender identities; and finally, a recognition of the sexual rights demanded in particular by the LGBTQIA+ movement. The omnipresence of screens and remote interactivity also herald other upheavals. New technologies are leading us toward what we might call cybersexuality. From now on, there is no longer just one recognized way of living one’s sexual life [129]. Sexuality is an integral part of this “acceleration of history.”

In this ever faster-paced world, how can we educate children and young people about sexuality, while political debates persist about what is public and what is private? And above all, how can we avoid becoming the guardians of morality in our pluralistic culture [6]?

Today, the international model of CSE Approach 3, designed to be equitable and evidence-based, claims it has an answer [64], with ready-to-use strategic recommendations to speed up its implementation and effectiveness at national level [150]. Despite international consensus, its implementation faces multiple sociocultural, political, and systemic obstacles [151]. At the top of the list of current challenges at different decision-making levels are the following priorities:

Regarding international intergovernmental and nongovernmental organizations and the WAS

1. Better master strategies for implementing sexuality education programs, apply implementation science, and more specifically implementation science communications [152], to improve the impact of sexuality education in schools, other educational settings, and the media.

2. Fund high-quality, up-to-date teaching for educators.

3. Create an experts’ center to award quality labels to teacher training centers, schools, and other stakeholders (similar to a dynamic accreditation system).

Regarding curriculum content

1. Apply Approach 4 (ECSCS), which enriches the CSE Approach 3 with educational or financial incentives.

2. Prepare for the new sexual revolutions: design and critically analyze the teaching of new sexualities linked to new technologies.

3. Continuously improve teaching content by opening up to the Sexocorporal Approach [153], which aims to provide an in-depth understanding of a person’s sexual functioning, to help them improve the quality of their sexual arousal and the sexual pleasure that accompanies it. Also open up to other ways of teaching sexuality: the sexual practices of millennial wisdoms (Tao [154] and Tantra [155]).

Regarding teaching-methods designers

1. Make teaching more stimulating through playful pedagogy. Facilitate educators’ work by providing them with ready-to-use training courses or information banks that can be tailored to the field [150, 156]. Make the most of digital media such as Twitter, Instagram, Facebook, and TikTok, as well as television, to disseminate attractive, didactic messages capable of orienting young people toward more liberal public health objectives, and filling their gaps in sex education.

2. Encourage the creation of maturity grids that can be used by each young person to determine the priority themes that are appropriate for his or her stage of development.

3. Create and award quality labels, based on quality criteria, to schools, educators, influencers and peers.

Regarding teachers

1. Train at quality-labeled training centers.

2. Be clear about one’s own sexuality and the one being taught (open-mindedness, discretion, impartiality, ability to stand back…). Avoid setting a particular sexual orientation or lifestyle as the norm. Avoid taking sides in political and cultural wars.

3. Create discussion groups between educators as a place to share mutual support, and talk about failures and successes.

Regarding parents

1. Since the new information and communication technologies can give an additional impression of loss of direct control, leading to “moral panic,” replace this direct control and the emphasis on reserve and restraint with a discourse based on individual responsibility [157].

2. Training in intrapersonal relationships: emotional intelligence, self-awareness, and self-confidence. Open up to sexuality and its various forms of expression.

3. Refer children to quality-labeled educational structures.

Regarding young people and teenagers

1. Follow quality-labeled training courses, according to the results of the maturity grid corresponding to each individual’s needs and demands.

2. Learn to tell the difference between reality and fiction, especially when pornography meets virtual reality [157].

3. Set up peer exchange groups.

As clinical sexologists and teachers, we dare to take up these challenges.

“In the 21st century, living, loving and enjoying has become an entirely different adventure from that of times gone by [129].”

6. Conclusions

Sexuality education today remains a controversial subject in families and schools, as well as in political, philosophical, and religious circles, as illustrated by the examples we have gathered. We set out to trace its evolution from the 1900s to early 2023, in a context limited to the Western world and culture. This historical journey has enabled us to understand the issues surrounding sex education and how they have evolved over time. In particular, it highlighted the arguments that led to questioning heterosexuality as the sole reference point for social behavior. The path taken has also led to modeling three main approaches to sexuality education. Among the milestones along the way are the positions adopted by international organizations, following debates aimed at giving a positive, protective meaning to sexuality by introducing the notion of sexual health. These positions are a reaction to the moral pedagogy adopted by the first half of the twentieth century’s sex education pioneers. These international bodies have also committed themselves to establishing sexual rights, with a view to protecting women and children from sexual violence, preventing discrimination based on sexual orientation, and recognizing gender identities, LGBTQIA+ communities, and alternatives to the cis-heteronormative model. All these values were introduced in the third and most recent approach to sex education (Approach 3). The literature was then analyzed to determine the impact of all three approaches. It was concluded the most promising is the third (Approach 3) and most recent approach. However, young people are expressing more and more needs and demands. They want to acquire more psychological, emotional, and erotic skills to cultivate healthy relationships, paving the way for safe and pleasurable sexual experiences. That is why we are proposing a fourth and new approach, also based on an evidence-based approach (Approach 4). It includes the third approach in its entirety but is enriched by meeting young people and adolescents’ concerns. It introduces a new theme in its own right: intrapersonal relationships. Based on the science of emotions, this approach helps build self-awareness and self-confidence. Once such skills have been acquired, they are reflected, among other things, in better practice of consent, and prevention of inequality, sexual violence, and discrimination. This fourth approach adds complementary topics to the theme of sexuality and sexual behavior, fostering better knowledge, skills, and know-how in intimate and sexual relationships by opening up more openly to sexual pleasure and desire. This complementary education offers greater chances of improving young people and adolescents’ mental, sexual, and emotional health. Last but not least, challenges are being thrown down to international bodies, educational designers, teachers, parents, and young people and teenagers alike. However, there are still fields yet to be explored that we are barely glimpsing: the cybersexual, heralding new sexual paradigms, and the silently but surely emerging new trend of adopting asexuality and abstinence.

Acknowledgments

The authors would like to thank Professor Magali Pirson, Director of Health Economics, Hospital Management and Nursing Research Dept, School of Public Health, Brussels Free University and Catherine Bouland, President of School of Public health, Brussels Free University for their unconditional support of this work. The authors would also like to thank Didier Dillen, journalist, and Wauthier Robyns for proof-reading the chapter and Anne-Catherine Dumont for her help in drawing up the tables and presenting the references.

Conflict of interest

The authors declare no conflict of interest.

Funding

The Open Access Publication Fee is supported by the Georgine Verschaeve Fund, School of Public Health, Free University of Brussels.