Our understanding of sexuality education is ever evolving, and differences exist in the terminology, definitions and criteria employed across various international documentation relating to SE (cf. Iyer and Aggleton, 2015; European Expert Group on Sexuality Education, 2016). While the term comprehensive sexuality education (CSE) has, in the last decade or so, come to be widely employed (WHO Regional Office for Europe and BZgA, 2017; United Nations Educational Scientific and Cultural Organisation [UNESCO], 2018), given its more recent common usage, for the purpose of this paper, sexuality education (SE) is the broader term employed.

An international qualitative review of studies which report on the views of students and experts/professionals working in the field of SE (Pound et al., 2017) provides recommendations for effective SE provision. According to that review, effective SE provision should include: The adoption of a “sex positive,” culturally sensitive approach; education that reflects sexual and relationship diversity and challenges inequality and gender stereotyping; content on topics including consent, sexting, cyberbullying, online safety, sexual exploitation, and sexual coercion; a “whole-school” approach and provide content on life skills; non-judgmental content on contraception, safer sex, pregnancy and abortion; discussion on relationships and emotions; consideration of potentially risky sexual practices and not over-emphasize risk at the expense of positive and pleasurable aspects of sex; and the production of a curriculum in collaboration with young people. Similarly, Goldfarb and Lieberman’s (2021) systematic review provides support for the adoption of comprehensive SE that is positive, affirming, inclusive, begins early in life, is scaffolded and takes place over an extended period of time.

While there are a variety of sources from which students access information for SE, and diversity in respect of students expressed preferences with regards to SE sources (Turnbull et al., 2010; Donaldson et al., 2013; Pound et al., 2016), the formal education system remains a significant site for universal, comprehensive, age-appropriate, effective SE. Teachers are particularly well-positioned to provide comprehensive SE and create a climate of trust and respect within the school (World Health Organisation [WHO]/Regional Office for Europe & Federal Centre for Health Education BZgA, 2010, 2017; Bourke et al., 2022). Qualities of the teacher and classroom environment are associated with increased knowledge of health education, including SE, for students. Murray et al. (2019) found that the teacher being certified to teach health education, having a dedicated classroom, and having attended professional development training were associated with greater student knowledge of this subject. Inadequate training, embarrassment and an inability to discuss SE topics in a non-judgmental way have been cited as explanations provided by students as to why they would not consider teachers suitable or desirable to teach SE (Pound et al., 2017).

Walker et al. (2021) in their systematic review of qualitative research on teachers’ perspectives on sexuality and reproductive health (SRH) education in primary and secondary schools, reported that adequate training (pre-service and in-service) was a facilitator that positively impacted on teachers’ confidence to provide school-based SRH education. These findings highlight the importance of quality teacher professional development, commencing with initial teacher education (ITE), for the provision of comprehensive SE. Consequently, ITE has increasingly been proposed as key in addressing the global, societal challenge of ensuring the provision of high-quality SE.

Teacher education provides substantial affordances to respond to the opportunities and challenges presented in the area of SE (WHO Regional Office for Europe and BZgA, 2017). Furthermore, a research-informed understanding of teacher education is emphasized to better support teacher educators in their work with student teachers (Swennen and White, 2020).

Quality ITE provides a strong foundation for teachers’ delivery of comprehensive SE and the creation of safe and supportive school climates. Research has found that teacher professional development in SE is a significant factor associated with the subsequent implementation of school-based SE (Ketting and Ivanova, 2018). A recent Ecuadorian study reported that student teachers held a relatively high level of confidence in terms of their perceived ability to implement SE and to address specific CSE topics. Furthermore, favourable attitudes toward CSE, strong self-efficacy beliefs to implement CSE, and increased confidence in the ability to implement CSE were significantly associated with positive intentions to teach CSE in the future. Insufficient mastery of CSE topics, however, may temper student teachers’ intentions to teach CSE (Castillo Nuñez et al., 2019). Internationally, research suggests there is inconsistency in the provision of SE in ITE and that access to professional development in SE in ITE, and after qualification, needs substantial development (United Nations Educational Scientific and Cultural Organisation [UNESCO], 2009, 2018; Ketting et al., 2018; O’Brien et al., 2020).

Research is thus warranted to explore aspects at the institutional, programmatic and student-teacher level at ITE to address issues regarding the provision, and barriers to SE provision during ITE. Contemporaneous to the current review, O’Brien et al. (2020) undertook a systematic review of teacher training organizations and their preparation of student teachers to teach CSE. They found that teacher training organizations are often strongly guided by national policies and their school curricula, as opposed to international guidelines. They also found that teachers are often inadequately prepared to teach CSE and that CSE provision during ITE is associated with greater self-efficacy and intent to teach CSE in schools. The importance of ITE with regards to the provision of SE cannot be underestimated. Teachers are in an optimal position to provide age-appropriate, comprehensive and developmentally relevant SE to all children and young people.

The current systematic review will assess the provision of SE to student teachers in ITE and how this relates to the relevant knowledge, attitudes and skills required of sexuality educators as proposed by the international guidelines produced by the WHO Regional Office for Europe and BZgA (2017). The WHO Regional Office for Europe and BZgA (2017) Training Matters: Framework of core competencies for sexuality educators adopts a holistic definition of core competencies, espousing an understanding of teacher competencies as “…overarching complex action systems” and as multi-dimensional, made up of three components: attitudes, skills and knowledge (WHO Regional Office for Europe and BZgA, 2017, p. 20). This framework outlines a set of general competencies, together with more specific attitudes, skills and knowledge competencies for sexuality educators. Attitudes, which may be explicit or implicit, are understood as a factor pertaining to the influencing and guiding of personal behaviour. Skills are understood in terms of the abilities educators can acquire which enables them to provide high-quality education. While knowledge is understood as professional knowledge (pedagogical knowledge, content knowledge and pedagogical subject knowledge) in all relevant areas required to deliver high-quality education. Overall, the framework endorses a holistic and multi-dimensional approach which focuses on sexuality educators and the inter-related competencies, in relation to the knowledge, attitudes, and skills that they should have, or need to develop to become effective teachers of SE.

The current study aimed to systematically review existing empirical evidence on the provision of SE for student teachers in the context of ITE.

The objectives were:

Articles were included in the review subject to adherence to specific inclusion criteria. An overview of inclusion criteria is outlined in Table 1.

A three-reviewer process was employed. Searches were conducted in August 2019 on five databases selected for their ability to provide a focused search within the disciplines of education (ERIC and Education Research Complete), psychology (PsycINFO), and multi-disciplinary research in the disciplines of health/public health (Web of Science and MEDLINE).

Reviewers’ selected keywords from two domains, namely ITE and SE as outlined in Table 2, for the searches. Search terms for each domain were combined using the Boolean search function “AND.”

Where possible, limits were applied to include articles from peer reviewed journals as outlined in Table 3.

In accordance with Boland et al. (2017), a pilot screening of a sample of titles and abstracts were completed by two reviewers to assess the inclusion and exclusion criteria. All titles and abstracts were then screened using Abstrackr software (Abstrackr, 2010, accessed 2019; Wallace et al., 2010). A selection of abstracts were then cross checked by two reviewers. The final selection involved a three reviewer process. Duplicates and references which did not meet the eligibility criteria were removed at this stage. Full text papers of the remaining articles were obtained, where possible. All three reviewers blindly screened the texts of the remaining articles. Consensus was reached that 15 articles met the criteria for this review. Two experts in the field of SE reviewed the list of 15 articles to ensure there were no outstanding papers for consideration within the parameters of the review. No additional papers were identified.

A data extraction template was devised in accordance with Boland et al.’s (2017) recommendations. Information was collected on each study regarding: participant characteristics (data on participant gender, age, programme and institution of study, ethnicity, socio-economic status and religion were extracted, where provided); whether the studies examined programmatic input and if so the duration/extent of input; theoretical and conceptualization of SE within the programme; topics covered; whether this was a compulsory or elective programme; and whether the study addressed the WHO-BZgA competencies of knowledge, attitudes and skills of student teachers during ITE (WHO Regional Office for Europe and BZgA, 2017). One lead author was contacted for the purpose of data collection and provided further information regarding their study.

A qualitative synthesis was conducted; the purpose of which was to provide an overview of the evidence identified regarding research on the provision of SE in the ITE context. The findings of the reviewed studies were synthesized following consideration of the key learnings and recommendations from the studies and consideration of the WHO Regional Office for Europe and BZgA (2017) competencies of knowledge, attitudes, and skills necessary for the provision of SE at ITE. The WHO Regional Office for Europe and BZgA (2017) framework was selected to support the categorization and analysis of findings as it was developed by global experts in the field and is thus, an international standard for SE. While there are limitations to the use of this framework, it offered the ability to categorize and analyze findings through a multi- dimensional lens of knowledge, attitudes, and skills.

The Mixed Methods Appraisal Tool (MMAT) (Pluye et al., 2009; Hong et al., 2018) was used to appraise the quality of papers by two reviewers. This tool has been found to be reliable for the appraisal of qualitative, quantitative and mixed methods studies (Pace et al., 2012; Taylor and Hignett, 2014) and has been successfully used in previous systematic reviews (e.g., McNicholl et al., 2019). For each paper, the appropriate study design was selected (i.e., 1. Qualitative, 2. Quantitative randomized controlled trials, 3. Quantitative non-randomized, 4. Quantitative descriptive, and 5. Mixed methods). Next, the paper was assessed using the checklist associated with the study design (see Appendix A for overview of checklist). For example, if the study was categorized as 4. Quantitative descriptive, the study was assessed against the five criteria (4.1–4.5) associated with this study design. An example of a question on the checklist includes “Are the measurements appropriate?” criteria were reported as “met,” “not met,” “cannot tell if criteria were met” or “criteria not applicable.” The results of the quality appraisal are presented in Table 4. The same numbering as the methodological quality criteria of Hong et al.’s (2018) study was used.

Fifteen articles reporting on thirteen empirical studies were included in the review (see Figure 1). Harrison and Ollis (2015) and Ollis (2016) articles are derived from the same dataset, as are Sinkinson and Hughes (2008) and Sinkinson (2009) articles. Given, however, that these articles refer to unique aspects of the particular studies, they have been described and discussed as separate studies in this review. An overview of the process of screening and study selection is outlined in Figure 1.

Six qualitative, five quantitative, and four mixed methods studies were reviewed. Where information was available, the research studies were identified as having been conducted predominantly in Australia, New Zealand, and South Africa. The studies were published between 1996 and 2016. Data was most frequently collected from one source; student teachers (n = 10) and teacher educators/course providers (n = 3). One study collected data from both student teachers and teacher educators/course providers (Johnson, 2014). The samples size of studies varied from three to 478 participants but were generally small (eight of the studies had fewer than 90 participants: Vavrus, 2009; Carman et al., 2011; Goldman and Coleman, 2013; Johnson, 2014; Harrison and Ollis, 2015; Brown, 2016; MacEntee, 2016; Ollis, 2016).

Seven studies assessed SE educational inputs at ITE, and three conducted content analysis of content covered on SE educational input at ITE. As the studies were predominantly descriptive and explorative in design, specific outcome variables were often neither defined nor addressed. Educational input studies were classified as examples of research which assessed a particular course, module, or lecture on SE at ITE. With regards to theoretical approaches that may have informed the educational input studies reviewed, three did not report a specific theoretical approach (Sinkinson, 2009; Gursimsek, 2010; MacEntee, 2016), and the remaining four reported that a critical approach was adopted (Vavrus, 2009; Harrison and Ollis, 2015; Brown, 2016; Ollis, 2016). An overview of study characteristics are presented in Table 5.

An overview of the results of the MMAT are presented in Table 4. All the papers in the review were empirical studies and therefore could be appraised using the MMAT. Predominantly the studies reviewed employed the use of qualitative methods, and of the mixed methods studies there was often an emphasis on the qualitative data. Generally, the quality of the mixed methods studies was varied with only a minority of these studies providing a rationale for the use of mixed methods and reporting on divergences between the qualitative and quantitative findings.

The rigour and quality of the qualitative research was also varied. An explicit statement of the epistemological stance adopted and detail of the analytical process were reported in a minority of studies. With regards to educational input studies, data was often collected only after the educational input was completed and thus behavioral change as a result of engagement in the educational input could not be ascertained (e.g., Harrison and Ollis, 2015; MacEntee, 2016; Ollis, 2016). Only one study employed a quasi-experimental design (Gursimsek, 2010), and in this case a purposive sample of student teachers who did not complete the SE course was selected as the control group. Within the remaining 14 studies there were no control groups, randomization, or concealment.

Findings are reported in relation to (a) institutional/programme level and (b) individual student teacher level aligned with the World Health Organisation (WHO Regional Office for Europe and BZgA, 2017) Training Matters: Framework of Core Competencies for Sexuality Educators. An awareness of the interaction of these aspects of student teachers’ development was informative in terms of structuring the findings.

The research studies reviewed predominantly focused on examining a particular educational input on SE during ITE (Sinkinson, 2009; Vavrus, 2009; Gursimsek, 2010; Harrison and Ollis, 2015; Brown, 2016; MacEntee, 2016; Ollis, 2016) or investigating the SE content covered during ITE (Rodriguez et al., 1997; McKay and Barrett, 1999; Carman et al., 2011). Fewer of the reviewed studies focused on student teachers’ skills to teach SE (e.g., Sinkinson, 2009; Vavrus, 2009; Harrison and Ollis, 2015; Goldman and Grimbeek, 2016; MacEntee, 2016) or student teachers’ attitudes regarding SE (e.g., Sinkinson and Hughes, 2008; Sinkinson, 2009; Vavrus, 2009; Gursimsek, 2010; Johnson, 2014; Brown, 2016). The findings of the studies were synthesized and categorized in relation to institutional/programmatic level or individual student teacher level. Findings which reflected responses and perceptions of student teachers were categorized as individual student teacher level. Institutional/Programme level related to studies assessing particular modules or comparing course content across programmes, and institutional level studies were categorized as studies where data was collected from multiple institutions. Individual student teacher level findings were reported in relation to the knowledge, attitudes, and skills competency areas required of sexuality educators. These competency domains, however, are not discrete entities or mutually exclusive. In taking a systemic approach, it is, therefore, acknowledged that they are dynamically interconnected, and influence and interact.

This systematic review sought to investigate the empirical literature on SE provision with student teachers during ITE. Fifteen articles, reporting on thirteen studies, from predominantly Western, English-speaking contexts met the criteria for review. The findings reveal the varied nature of the provision of SE during ITE for student teachers (Rodriguez et al., 1997; McKay and Barrett, 1999; Carman et al., 2011). This is consistent with the findings of O’Brien et al.’s (2020) systematic review which similarly found variability in the provision of SE for student teachers. The current reviewed studies document an examination of SE provision at institutional/programme level, and individual student teacher level. The latter studies, in the main, reflected student teachers’ experiences regarding a particular educational input on SE, and to a lesser extent related to an examination of student teachers’ general knowledge, attitudes, or skills regarding SE.

Along with the acknowledged need to provide educational input on SE in ITE, the findings reflect that SE is perceived of as more than a stand-alone curriculum subject. Recommendations from the reviewed studies in respect of educational input provide some support for a more embedded and intersectional approach to SE provision during ITE. Similarly, O’Brien et al.’s (2020) systematic review emphasized the need for greater collaboration, integration and consistency in provision of SE at ITE. ITE in SE is typically seen within the realm of student teachers who are going to qualify as health educators, however, there is a strong argument to make that all pre-service teachers require a fundamental understanding of SE. With regards to the current review, for example, Vavrus (2009) concluded that there is a need for teacher education programmes that extend curricular attention to gender identity formation and sexuality, beyond specific SE modules, as it was suggested that this will help student teachers better understand socio-cultural factors that influence their teacher identities. Harrison and Ollis (2015) acknowledged that—as student teachers may not have engaged with critical approaches to material previously and may not have been provided with adequate time to consider these interpretations of gender and power—programmes over an extended period of time and engagement with these topics across the curriculum may facilitate increased engagement and reflection on this content. The findings provide some support that more time invested in educational input programmes may be beneficial. Courses covered over a semester (Sinkinson, 2009; Gursimsek, 2010), for example, may be more beneficial than those covered over much shorter periods (Harrison and Ollis, 2015; Ollis, 2016).

The WHO Regional Office for Europe and BZgA (2017) states that an important pre-requisite to teaching SE is the ability and willingness of teachers to reflect on their own attitudes toward sexuality, and social norms of sexuality. Sexual Attitudes Reassessment or values clarification has been an integral part of sexology education and training since the 1990s (Sitron and Dyson, 2009). Indeed, many accreditation bodies set a minimum number of hours in this process-orientated exploration as a requirement for sexology or sexuality education work (Areskoug-Josefsson and Lindroth, 2022). This involves a highly personal internal exploration that is directed toward helping participants to clarify their personal values and provides opportunities for participants to explore their attitudes, values, feelings and beliefs about sexuality and how these impact on their professional interactions (Sitron and Dyson, 2009). This type of input would be valuable in the ITE space. The current findings indicate that educational inputs which facilitate self-reflection and the development of critical consciousness may be particularly beneficial and necessary in supporting student teachers to teach SE. Having the space and time to engage with one’s own belief systems, and experiences, can provide student teachers with insights regarding factors that shape identity and human interaction, which are fundamental to comprehensive SE. This is an important task for teachers and previously has been identified as a gap within existing teacher education programmes (Kincheloe, 2005, as cited in Vavrus, 2009).

With regards to pedagogical approaches for teaching SE during ITE, the findings indicate that the use of tutorial groups, small group face-to-face discussions, case studies, participatory visual methods, and the inclusion of guest speakers sharing their lived experiences may create less threatening, and more comfortable, environments for student teachers to engage with SE topics on a personal level (Johnson, 2014; Brown, 2016; Goldman and Grimbeek, 2016; MacEntee, 2016). These findings are somewhat consistent with existing evidence that supports experiential and participatory learning techniques for SE (e.g., United Nations Educational Scientific and Cultural Organisation [UNESCO], 2018; Begley et al., 2022). A lack of practical teaching experience was acknowledged by student teachers as a barrier to teaching SE topics (e.g., Vavrus, 2009; MacEntee, 2016). Given the reported (Ollis, 2016), and potential (Vavrus, 2009) benefits from engaging in the practice of teaching SE the inclusion of skills-based and practical teaching experience of SE or its proxy as a minimum, within the ITE context may be warranted.

There were some notable absences from the literature reviewed. Although there are examples of research in this review which refer to positive SE topics such as pleasure, sexual orientation, and gender identity, the studies in the main do not reflect an examination of topics fundamental to a CSE curriculum. Studies did not consider or examine the impact of the Internet and social media in relation to SE. Apart from May and Kundert’s (1996) study, the research did not reflect consideration of the provision of SE for students with diverse learning abilities and needs. Some studies considered correlational factors pertaining to student teachers’ attitudes regarding SE. These included gender, geographical location of upbringing (Gursimsek, 2010), and student teachers’ previous school experiences of SE (Sinkinson and Hughes, 2008; Vavrus, 2009). Overall, in the studies reviewed there was a dearth of research on student teachers’ attitudes about SE, and the inter-dependence of factors that may influence student teachers’ attitudes.

Given that this field of research is in its relative infancy, the findings which may be inferred from the educational input studies (Sinkinson, 2009; Vavrus, 2009; Gursimsek, 2010; Harrison and Ollis, 2015; Brown, 2016; MacEntee, 2016; Ollis, 2016), are tentative. These studies are generally informative regarding a particular topic or educational input but tend not to shed light on student teachers’ experiences. Furthermore, the findings from Carman et al.’s (2011) and Johnson’s (2014) studies, highlight the role of teacher educators in relation to SE provision being taught during ITE. Teacher educators provide vital support and facilitate new understandings and guidance in the context of SE and teacher professional development. Consistent with O’Brien et al. (2020), this review highlights the need to promote greater shared learning and evidence-based resources among teacher educators and ITE institutions.

This systematic review should be considered in light of its limitations. There is inherent risk of bias across studies given that only peer reviewed articles written in English were reported on. Consequently, a wealth of potential research may have been precluded from review and the findings of the studies will pertain to and potentially reflect the experiences of those in the global north and/or a Westernized view. The exclusion of grey literature such as dissertations and theoretical papers is indicative of publication bias. The very process of selecting inclusion and exclusion criteria is subjective and may facilitate the exclusion of minority voices, or creative methodologies for conducting and or presenting research. Through the exclusion of position papers or articles that do not make reference to empirical data, important voices to this conversation may have been limited/excluded.

Findings were discussed in relation to the competencies outlined by the WHO Regional Office for Europe and BZgA (2017). Although an international standard for SE, there are limitations to these guidelines. Our understanding of the provision of SE is continuously developing. In 2019, the Sex Information and Education Council of Canada (SIECCAN) updated their guidelines to include an emphasis on changing demographics in relation to sexual health, the need for sexual health educators to demonstrate awareness of the impact of colonialism on the sexual health and well-being of indigenous people, to recognize the impact of technology on sexual health education, to meet the needs of young people of all identities and sexual orientations, and the need to address the topic of consent within sex education. These aspects of SE are not reflected in the WHO Regional Office for Europe and BZgA (2017) guidelines, nor are they reflected in the studies reviewed. This is indicative of the dynamic and complex nature of the field of SE and specifically in ITE.

Given the design of the studies we cannot conclude that ITE experiences translate to teachers’ SE teaching practice. Some studies provided examples of the barriers student teachers can face in the translation of ITE experiences to classroom experiences (e.g., MacEntee, 2016). However, other than MacEntee (2016), examples of research with both student teachers and in-service teachers were not identified nor were longitudinal studies examining the progression from ITE to classroom experiences. Notably, upon screening the abstracts, the literature tended to assess SE received by medical and health care professionals, and there were far less examples regarding research with teachers in general and as may be garnered from this systematic review, a very limited amount of research conducted with student teachers in ITE. As ITE programmes do not routinely publish their course content, there is also a chance that such professional learning and development is being provided but not being reported. Furthermore, given that research on SE within an ITE context is a relatively novel field, diverse methodological approaches have been adopted and there appears to be limited reporting of the theoretical basis informing on this work which has implications for cross-study synthesis of findings. The studies included in this systematic review, predominantly employed qualitative designs and consequently were more idiosyncratic in their selected methodological approach.

Drawing on the findings from the systematic review the overarching recommendation is for more quality research on teacher professional development in the context of SE during ITE. Aspects which require further research attention are outlined below.

Along with the provision of educational input on SE at ITE, an embedded and intersectional approach to SE at ITE programme-level requires further exploration. If student teachers are to meet their future school students’ SE needs, a foundational element of teacher preparation must involve actively addressing issues that are linked to teacher confidence and comfort for delivering SE. The reviewed studies broadly indicate that opportunities for critical self-reflection, practice-oriented and small-group, dialogical, inclusive and participatory pedagogical approaches may be beneficial to adopt with regards to the provision of SE during ITE, however, further robust research is required to support this.

Larger scale, multi-dimensional, integrative studies employing rigorous methodologies to assess inter alia student teachers’ knowledge, attitudes, and skills, regarding sexuality during ITE including student teachers’ knowledge, comfort, confidence and preparedness to teach sexuality are warranted. Furthermore, research which is inclusive of both student teachers’ and teacher educators’ voices, is needed.

Adoption of a systemic approach examining individual-level and contextual factors relating to SE provision during ITE is needed to develop theoretically derived, research-informed, and evidence-based SE programmes at ITE. In order to improve the provision of SE at ITE an evaluation of provision must be in place for best practice to be achieved.

ITE provision needs to adopt a holistic approach when supporting teacher development. As documented by the WHO Regional Office for Europe and BZgA (2017) guidelines, this involves supporting the development and acquisition of relevant knowledge, attitudes and skills pertaining to SE. Although ITE in SE often focuses on student teachers who will qualify as health educators, it can be argued that all pre-service teachers require a fundamental understanding of SE. Furthermore, the SE provided during ITE should be nuanced to support LGBTI students, students with special educational needs and/or from diverse racial and cultural backgrounds (Whitten and Sethna, 2014; Ellis and Bentham, 2021; Michielsen and Brockschmidt, 2021). A series of indicators to assess the relevant factors pertaining to SE provision and how these indicators relate to the knowledge, attitudes, and skills required for sexuality educators would be helpful. Monitoring and evaluation of structural indicators such as the designated SE components of course programmes, whether courses are elective or core, whether practice elements are provided etc. would provide a baseline from which system change and improvements could be measured. This systematic review has provided tentative suggestions as to what may work to ensure best practice of SE during ITE. Further research is required to evaluate the outcomes associated with their implementation.