Encountering sexual and gender minority youth in healthcare: an integrative review

Aim To describe the encounters with sexual and gender minority (SGM) youth in healthcare based on the existing research. Background The development of sexual orientation and gender identity can create challenges in an SGM youth’s life, and they may need support from health professionals. Heteronormativity has been recognised as a barrier to the identification of diversity in sexuality and gender, and no previous literature review has studied heteronormativity thoroughly. Methods An integrative review following Whittemore and Knafl was conducted. A literature search was systematically undertaken in six databases (PubMed/MEDLINE, CINAHL, Cochrane Library, PsycINFO, Eric, and Academic Search Premier). Finally, 18 research articles were included. Data were analysed deductively with the theoretical framework from Stevi Jackson’s (2006) article to understand the role of heteronormativity in the healthcare of SGM youth. Findings The encounters with SGM youth consisted of two simultaneous themes. Heteronormative care included three elements: (1) the effect of heteronormativity on health professionals’ competence to work with SGM youth, (2) false assumptions about SGM youth, and (3) the influence of heteronormativity on encounters with SGM youth. Diversity-affirming care included two elements: (4) the considerateness of health professionals towards SGM youth and (5) inclusive care of SGM youth. Conclusion This review summarised how SGM youth were encountered in healthcare and how heteronormativity was affecting their healthcare. Furthermore, this review identified elements that supported diversity-affirming care. With diversity-affirming care, SGM youth may access the information and support they need from healthcare. Further research is needed about how diversity-affirming care can be applied to the healthcare of SGM youth and how elements of heteronormative care are occurring globally in the healthcare of SGM youth. The perceptions of transgender and other gender minority youth were under-represented in the studies and research needs to focus more on how they are encountered in healthcare.


Introduction
During adolescence, a period between the ages of 10 and 19 years, young people go through several physical, psychosocial, and sexual maturation changes, including the development of gender identity and sexual orientation (World Health Organization, 2017;World Health Organization, 2018a). Here, we use the term sexual and gender minority (SGM) youth to refer to adolescents whose sexual orientation is non-heterosexual and/or their gender identity is outside the female/male binary (Smalley et al., 2018). In adolescence, SGM youth may face challenges that are related to their identity (The Lancet, 2011;Bregman et al., 2013). They may face victimisation and bullying (Espelage et al. 2008;Huebner et al., 2015;Kosciw et al., 2015), as well as negative attitudes from peers and family (Bregman et al., 2013;Kosciw et al., 2015;Katz-wise et al., 2016;Puckett et al., 2017). To be able to face these challenges, SGM youth may benefit from the support of various professionals including health professionals (Reynolds, 2011). Appropriate support requires, for example, professionals' competency, respectful attitude, and ability to fulfil SGM youths' rights to information, privacy, confidentiality, and non-discrimination in healthcare (World Health Organization, 2015).
In healthcare, SGM people are often an invisible patient group (Fish and Bewley, 2010;McIntyre and McDonald, 2012). One reason for this is heteronormativity, defined as a general assumption that everyone is heterosexual and everything else is exceptional (Fish and Bewley, 2010;McIntyre and McDonald, 2012;Katz, 2014). Norms, including heteronormative ones, are factors that are generally thought to guide human actions (values, beliefs, assumptions). They operate within social dimensions such as cultural, institutional, sexual, and/or interpersonal. Heteronormativity defines normative ways of life as well as normative ways of sexuality. It can be examined from three aspects: gender, sexuality, and heterosexualness (Jackson, 2006). First, gender is a state of being female/male in social and cultural levels, and sex refers to biological levels of being female/male (Smalley et al., 2018). In heteronormativity, gender is usually seen through a binary, where man and woman are opposites completing each other. Gender includes acts that are assumed to cohere with biological sex normatively, such as women being feminine and men being masculine. Second, sexuality is supposed to cohere with gender, as in women and men sexually desiring each other as complementary genders. Finally, heterosexualness is both sexual acts that are 'natural and normal' and non-sexual acts, such as a heterosexual woman/man having a biological need to reproduce (Jackson, 2006). Thus, young people who have a sexual orientation and/or gender identity that cannot be understood through heteronormativity, may experience invisibility in different fields of society, including healthcare. There are no earlier literature reviews that have summarised the encounters with SGM youth in healthcare. Thus, the aim of this study was to describe the encounters with SGM youth in healthcare based on the existing research. Furthermore, this study focuses for the first time on the role of heteronormativity and its relation to encountering SGM youth in healthcare.

Problem identification
In the problem identification stage, a clear aim for the review was defined to support the following stages (Whittemore and Knafl, 2005). The aim was to describe the encounters with SGM youth in healthcare based on existing research, and, to make a comprehensive review, no time limit regarding publication date was set.

Literature search
The literature search stage includes precise planning and description of the search strategy a priori to maintain the rigour in the review (Torraco, 2005;Whittemore and Knafl, 2005). A systematic search was undertaken between the 24 th of November, 2017, and the 1 st of January, 2018, in six electronic databases: PubMed/MEDLINE, CINAHL, Cochrane Library, PsycINFO, Eric, and Academic Search Premier. Search phrases included combinations of key terms and free-text terms for the following concepts: sexual and gender minorities (e.g. homosexual, transgender persons), adolescents (e.g. youth, teen), and healthcare practices (e.g. school healthcare, adolescent health services). The detailed search strategy is in Table 1.
The inclusion criteria for the literature were as follows: (1) a scientific, peer-reviewed research article, (2) the publication language was English, (3) a focus on the perspectives of SGM youth in healthcare practices, or (4) a focus on the perspectives of health professionals working with SGM youth. In this review, health CINAHL AB ((MH "School Health Services + ") OR (MH "Nursing Care + ") OR (MH "Adolescent Health Services") OR (MH "School Health Nursing") OR "school health" OR "school healthcare" OR "school nurs*" OR "nursing" OR nurse* OR "healthcare") AND ((MH "Adolescence + ") OR (MH "Young Adult") OR adolescen* OR youth OR teen* OR young) AND ((MH "Transgender Persons + ") OR (MH "GLBT Persons + ") OR (MH "Gay Persons + ") OR (MH "Homosexuality") OR (MH "Gay Men") OR (MH "Lesbians") OR (MH "Bisexuality") OR homosex* OR lesb* OR bisex* OR transsex* OR transgender* OR queer OR intersex* OR asex*)) professionals were defined as graduated professionals who are working in the field of healthcare. The article was excluded if (1) more than 50% of SGM youth participants were younger than 10 years or older than 19 years, (2) the study focussed on a medical condition (e.g. HIV), or (3) the study focussed on a health problem (e.g. tobacco or substance use). The latter two exclusion criteria based on the perception that studies focussing solely on a medical condition or a health problem do not include the perspectives of SGM youth or health professionals. The total results of the systematic search included 1421 scientific, peer-reviewed research articles that were published in 1978-2017. Screening of the articles was done first at the title and the abstract level, and second at the full text level (Figure 1). Two authors screened the articles independently. During the screening process, the authors discussed the eligibility of the remaining articles. Some articles were excluded because the abstract was not available, or an exclusion criterion was fulfilled. One article was considered as 'a borderline case' because it was uncertain if 50% of the participants were 10-19 years old due to age group categories. However, because 40% of the participants were certainly 10-19 years old and the article was congruent with other inclusion criteria and the aim of the study, the article was included. Finally, 18 scientific research articles were included in the analysis.

Data evaluation
The chosen articles were extracted, and the quality of studies was appraised (Whittemore and Knafl, 2005). The articles were extracted into two tables with key information about the studies. Table 2 describes studies conducted from SGM youth's perspectives, and Table 3 includes studies conducted from health professionals' perspectives (Tables 2 and 3).
To appraise the quality of the studies, the Mixed Methods Appraisal Checklist (MMAT) tool was used. Pluye et al. (2011) designed the MMAT tool to appraise the quality of qualitative, quantitative, and mixed methods studies in literature reviews (Pluye et al., 2011;Souto et al., 2015). A mixed methods study is a study that uses both qualitative and quantitative data collection methods, based on the definition in the MMAT tool. Quality appraisal started with evaluating criteria that were common to all studies (research questions) and specific to research design (data collection and findings). For each criterion, response options were 'yes', 'no', or 'can't tell'. Next, to score the quality, all 'yes' answers were summed, and then divided by the total number of criteria. Finally, the number was multiplied by 100, giving the total percentage score of quality. Two authors (ML, AP) did the quality appraisal independently and, through discussion, achieved consensus about the quality. These final scores were summed into Tables 2 and 3.

Data analysis
A deductive descriptive data analysis was performed (Whittemore and Knafl, 2005;Whittemore, 2007). Jackson's (2006) theoretical article was used as a theoretical framework to understand the role of heteronormativity in the healthcare of SGM youth. Based on this understanding, the elements addressing heteronormativity and breaking heteronormativity were identified from the studies, listed, and compared together. Finally, two themes with five elements related to heteronormativity and the encounters with SGM youth were identified.

Database
Search phrase services" OR "school health" OR "school healthcare" OR "school nurs*" OR "nursing" OR nurse* OR healthcare) AND (DE "TEENAGERS" OR DE "ADOLESCENCE" OR DE "YOUTH" OR adolescent OR youth* OR teen* OR young) AND (DE " LGBT high school students" OR DE "BISEXUAL high school students" OR DE "GAY high school students" OR DE "TRANSGENDER high school students" OR DE " LGBT youth" OR DE "BISEXUAL youth" OR DE "GAY youth" OR DE "LESBIAN youth" OR DE " LGBT teenagers" OR DE " LGBT young adults" OR DE "TRANSGENDER youth" OR DE " LGBT people" OR DE LGBT students" OR DE " LGBT youth" OR DE "MINORITY LGBT people" OR DE "TRANSGENDER people" OR homosex* OR lesb* OR bisex* OR transsex* OR transgender* OR queer OR intersex* OR asex*) Some studies did not categorise identities at all (Rasberry et al., 2015;Rose and Friedman, 2017). East and El Rayess (1998) and Rose and Friedman (2013) focussed solely on sexual minority youth which they defined as gay, lesbian, and bisexual youth. Ginsburg et al. (2002) and Snyder et al. (2016) defined transgender as a sexual orientation. Related to gender identity, the term cisgender was identified in the studies of Arbeit et al. (2016) and Shires et al. (2017).

Quality assessment
The quality scores ranged from 25% to 100% according to the MMAT tool. This range indicated that the quality of the studies was low to excellent. The most frequent score was 75% (n = 7), and the quality of Scherzer's (2000) and Lefkowitz and Mannell (2017) studies was assessed as excellent with a score of 100%. The quality appraisal did not exclude any articles, but it gave an overview of the quality in studies in contrast with the results (Pluye et al., 2011).

The themes of encountering SGM youth in healthcare
Based on the data analysis, the encounters with SGM youth in healthcare consisted of two themes heteronormative care and diversity-affirming care. This shows how the healthcare of SGM youth does not only include either heteronormative or heteronormativity-breaking elements. Both heteronormative care and diversity-affirming care have their own specific elements. These five elements include (1) the effect of heteronormativity on health professionals' competence to work with SGM youth, (2) false assumptions about SGM youth, (3) the influence of heteronormativity on encounters with SGM youth, (4) the considerateness of health professionals towards SGM youth, and (5) inclusive care of SGM youth. The first three elements describe the heteronormative care, and the last two describe the diversity-affirming care. The encounters with SGM youth in healthcare can include elements from both themes ( Figure 2).
Heteronormative care Element 1. The effect of heteronormativity on health professionals' competence to work with SGM youth Most studies identified problems in health professionals' competence to work with SGM youth. These problems can be related to heteronormativity. Scherzer (2000), Rasberry et al. (2015), and Rose and Friedman (2017)

n = 19
Records excluded n= 8 • Other perspective than healthcare practices n = 1 • Other age group than adolescents n = 3 • More than 50% participants other than adolescents or health professionals n = 3 • Low quality as a research article n = 1

Records after duplicates removed
United States Help inform school-centred strategies for connecting Black and Latino young men who have sex with men (YMSM) to HIV and STD prevention services. This was provided by describing (1) the willingness and safety of YMSM to discuss sexual health and sexual orientation-related topics, (2)  Semi-structured interviews Five main themes arose from the interviews: (1) need for increased quantity of sexual communication, (2) need for increased quality of sexual communication, (3) concerns about confidentiality/ privacy, (4) comfort, and (5) inclusivity diverse sexual orientations or gender identity issues, such as the gender-affirming process was unfamiliar to professionals. In several studies, health professionals reported their lack of knowledge and skills to provide care for SGM youth (East and El Rayess, 1998;Sawyer et al., 2006;Kitts, 2010;Rose and Friedman, 2013;Knight et al., 2014;Mahdi et al., 2014;Torres et al., 2015;Vance et al., 2015;Shires et al., 2017). For example, Torres et al. (2015) and Shires et al. (2017) found that health professionals were not familiar with gender-affirming medical care for transgender youth and did not know how and when to proceed with this.

Element 2. False assumptions about SGM youth
Health professionals may have several false assumptions about SGM youth. The most frequently reported assumption in the studies was a heterosexual assumption (East and El Rayess, 1998;Scherzer, 2000;Ginsburg et al., 2002;Kitts, 2010;Arbeit et al., 2016;Fuzzell et al., 2016). Scherzer (2000) and Arbeit et al. (2016) identified that heterosexual assumption led to a situation where SGM youth did not receive information that was relevant to them. Assumptions were also linked to certain SGM youths' identities.
In two studies, being gay was linked to having HIV (East and El Rayess, 1998;Ginsburg et al., 2002), and Lefkowitz and Mannell (2017) found that some health professionals connected transgender youth with homosexuality, unstable mental health, placement of gender identity within female/male binary, and the presumption that transgender identity was an experimentation or stage of confusion in adolescence. The influences of heteronormativity were described not only as negative attitudes and disrespectful behaviour from health professionals but also as mistreatment of SGM youth. Negative attitudes appeared as patronising (Ginsburg et al., 2002;Rasberry et al., 2015;Fuzzell et al., 2016;Snyder et al., 2016), stigmatising, or marginalising SGM youth (Scherzer, 2000;Ginsburg et al., 2002;Arbeit et al., 2016;Fuzzell et al., 2016;Rose and Friedman, 2017). Disrespectful behaviour appeared in various ways. Sometimes, health professionals underestimated SGM youths' identities and abilities to define themselves because of their young age (Scherzer, 2000;Mahdi et al., 2014;Arbeit et al., 2016;Snyder et al., 2016). Some studies reported that when SGM youth disclosed their identity, health professionals reacted to this disclosure with varying, even intense, ways. The reports included professionals being confused (Fuzzell et al., 2016), reserved (East and El Rayess, 1998), or unable to interact with the SGM youth (Knight et al., 2014;Mahdi et al., 2014). In Snyder et al.'s (2016) study, SGM youth described that some health professionals ignored their disclosure, suggested the youth changing sexual orientation to heterosexual (Snyder et al., 2016), or gave health information based on their heteronormative attitudes. Scherzer (2000) also found the latter reaction in her study. Ginsburg et al. (2002), Scherzer (2000), and Arbeit et al. (2016) discovered that a SGM  The majority of physicians would not discuss regularly about youth's sexual orientation, sexual attraction, or gender identity when they took a sexual history from a sexually-active adolescent. Some physicians were not aware of an association between LGBTQ youth and suicide. The majority of physicians indicated a lack of skills to address issues of sexual orientation with adolescents, and they agreed that sexual orientation needs to be addressed more often with adolescents 25 Rose and Friedman  youth's disclosure to a health professional had, in some cases, resulted in an intense reaction from a health professional, such as leaving from the appointment room. Heteronormativity also influenced the results of SGM youths' healthcare. False assumptions about SGM youth led to situations that can be described as mistreatment. In seven studies, information and care to SGM youth were given only from a heterosexual aspect, and health professionals did not ask nor discuss the youth's sexual orientation (Kitts, 2010;Rose and Friedman, 2013;Arbeit et al., 2016;Fuzzell et al., 2016;Snyder et al., 2016;Lefkowitz and Mannell, 2017;Rose and Friedman, 2017). Health professionals in Lefkowitz and Mannell's (2017) study had taken STD test samples incorrectly from transgender youth because of their confusion about the youth's sexual organs.

Diversity-affirming care
Element 4. The considerateness of health professionals towards SGM youth Health professionals can also work beyond the influence of heteronormativity. Their encounters with SGM youth can be described as considerate. Considerateness included both mentions from health professionals and SGM youth in the studies. Several studies found that open-mindedness was important for SGM youth (Ginsburg et al., 2002;Hoffman et al., 2009;Rasberry et al., 2015;Arbeit et al., 2016;Lefkowitz and Mannell, 2017), as well as equality and respect from health professionals (Ginsburg et al., 2002;Hoffman et al., 2009;Snyder et al., 2016). Both professionals and SGM youth indicated that considerate health professionals can create a comfortable and safe environment for SGM youth (Scherzer, 2000;Ginsburg et al., 2002;Arbeit et al., 2016;Snyder et al., 2016;Lefkowitz and Mannell, 2017). Considerateness came out as health professionals' genuine care about SGM youth and their health in Torres et al. (2015) results. Knight et al. (2014) and Lefkowitz and Mannell (2017) found that health professionals were able to identify diversity in sexuality and gender, and that health professionals supported the youth in decision-making and reaching sexual health information. In four studies, health professionals who indicated having knowledge gaps about SGM youth and their health, considered training and education about these topics to be significant (East and El Rayess, 1998;Knight et al., 2014;Vance et al, 2015;Shires et al., 2017).
Element 5. Inclusive care of SGM youth Torres et al. (2015), Arbeit et al. (2016), andFuzzell et al. (2016) highlighted the importance of acceptance and normalisation of diversity in sexuality and gender when organising inclusive care for SGM youth. In other studies, inclusive care was considered from three aspects: health professionals, information, and healthcare setting.
Inclusive health professionals were described as users of inclusive language (e.g. the neutral partner than the assumed heterosexual opposite) (Hoffman et al., 2009;Fuzzell et al., 2016), who asked which pronouns gender minority youth preferred (Torres et al., 2015;Fuzzell et al., 2016). Several studies indicated that inclusive health professionals had knowledge about issues related to SGM youths' health and well-being (Ginsburg et al., 2002;Hoffman et al., 2009;Rasberry et al., 2015;Torres et al., 2015;Fuzzell et al., 2016;Snyder et al., 2016;Rose and Friedman, 2017) and diversity in sexuality and gender (Ginsburg et al., 2002;Knight et al., 2014;Torres et al., 2015;Arbeit et al., 2016;Fuzzell et al., 2016). Related to interpersonal skills, inclusive health Lefkowitz and Mannell (2017 More than half of paediatricians would refer transgender youth to another provider regarding puberty blockers and hormone therapy. Barriers to caring transgender youth included a lack of time, a lack of training in transgender-specific care, and a lack of familiarity with guidelines for genderaffirming care professionals were described as having an ability to meet the youth sensitively (Scherzer, 2000;Hoffman et al., 2009;Snyder et al., 2016). Some studies stated that health professionals needed an ability to promote open discussion with SGM youth (Rose and Friedman, 2013;Rasberry et al., 2015;Arbeit et al., 2016;Fuzzell et al., 2016;Snyder et al., 2016).
Inclusive information consisted of topics that were specific to SGM youths' health, as well as information related to other perspectives in life. Many studies mentioned the sexual health of SGM youth as an important health information topic (Ginsburg et al., 2002;Kitts, 2010;Arbeit et al., 2016;Snyder et al., 2016;Rose and Friedman, 2017), as well as information about sexual orientations (Ginsburg et al., 2002;Kitts, 2010;Snyder et al., 2016), gender identities (Ginsburg et al., 2002), and mental health (Ginsburg et al., 2002;Hoffman et al., 2009;Snyder et al., 2016). Ginsburg et al. (2002), Hoffman et al. (2009), andArbeit et al. (2016) reported SGM youth were willing to get information about how to talk with parents about their identities, and in the studies of Ginsburg et al. (2002) and Arbeit et al. (2016), SGM youth were interested about human rights issues related to them.
Inclusive healthcare settings were described in six studies. First, Ginsburg et al. (2002), Hoffman et al. (2009), Torres et al. (2015, and Fuzzell et al. (2016) mentioned that an inclusive healthcare setting needed to have a sign of inclusivity for SGM youth, such as stickers (rainbow or pink triangle), informational leaflets and posters, or SGM-oriented magazines. Second, three studies recommended that medical forms should use inclusive language (Torres et al., 2015;Fuzzell et al., 2016;Snyder et al., 2016) and an option for gender minority youth to define their gender identity outside of the female/male binary (Knight et al., 2014;Fuzzell et al., 2016). Third, SGM youth who participated in the study of Ginsburg et al. (2002), Hoffman et al. (2009), or Snyder et al. (2016, indicated an interest in health clinics that specialised in SGM youth. However, Ginsburg et al. (2002) and Hoffman et al. (2009) also described how some SGM youth thought these clinics were isolating and labelling from other young people.

Discussion
This integrative review was the first describing the encounters with SGM youth in healthcare based on the existing research. This review revealed insights about the role of heteronormativity in the encounters between SGM youth and health professionals. It also identified elements of diversity-affirming care. Thus, this review discovered that the diversity of SGM youth is not always recognised, but elements supporting diversity in healthcare also exist. We suggest that further research could study how diversityaffirming care elements could be applied to the healthcare of SGM youth. The review focused on heteronormativity, which is based on feminist research (Jackson, 2006). Future research could focus on another feminist research approach, intersectionality. Intersectionality identifies how different identities such as race, class, gender and sexuality intersect each other, and how social power related to these identities affect to person's status for example oppressively (Van Herk et al., 2011). Intersectionality could raise up new issues in the healthcare of SGM youth, since they can be a diverse group from other aspects besides gender and sexuality (Jackson, 2006).
One of the most commonly reported element of heteronormativity was a heterosexual assumption about SGM youth in healthcare (East and El Rayess, 1998;Scherzer, 2000;Ginsburg et al., 2002;Kitts, 2010;Arbeit et al., 2016;Fuzzell et al., 2016). This issue has been recognised in previous literature (O'Neill and Wakefield, 2017;Brooks et al., 2018), and its influences for SGM youth were identified in this review. One example of the influence of the heterosexual assumption in healthcare is lack of information that is relevant to SGM youth. This was reported often-a total of 11 studies in this review. Earlier literature has also found the same issue in the healthcare of SGM youth (Garbers et al., 2017;Steinke et al., 2017). This aspect reflects how heteronormativity still affects different fields in life including healthcare. SGM youth often have limited protective support resources (Hirsch et al., 2010), and if they cannot access relevant information in healthcare, they may look for it elsewhere, such as from online resources (Gay, Lesbian & Straight Education Network et al., 2013;Steinke et al., 2017). The results of this review showed that SGM youth desired to have access to information related to their health and well-being from open-minded, youth-respecting health professionals (Ginsburg et al., 2002;Hoffman et al., 2009;Rasberry et al., 2015;Arbeit et al., 2016;Snyder et al., 2016). Thus, SGM youth need interactions with adults about their development, health, and well-being. Online resources can support, enable, or even enhance this interaction.
An integrative review has the potential to describe the complexity of a phenomenon from various perspectives (Whittemore and Knafl, 2005). In this integrative review, over half of the studies were conducted from health professionals' perspectives (East and El Rayess, 1998;Sawyer et al., 2006;Kitts, 2010;Rose and Friedman, 2013;Knight et al., 2014;Mahdi et al., 2014;Torres et al., 2015;Vance et al., 2015;Lefkowitz and Mannell, 2017). This shows how SGM youth were often studied from an external view, and the description of the role of heteronormativity might be, at some point, biased in this review. However, the review is the first to focus on a specific aspect in the healthcare of SGM youth, and the results give a new understanding about heteronormativity that evidently affects this youth minority group. Achieving this understanding is significant, when health professionals want to understand diversity in young people, improve their awareness of SGM youth and their challenges in life, and provide care ensuring healthy transitions to adulthood (Moon et al., 2002). The transferability of the results may be limited to other healthcare systems and settings besides American, Canadian, or United Kingdom (Polit and Beck, 2010), since healthcare policies and economic factors related to healthcare can vary between countries. However, the results show that more attention is needed regarding how SGM youth are encountered in different healthcare systems globally, and how heteronormativity affects the equality in adolescents' healthcare. Neither can we forget that even if the recognition of same sex relationships has advanced globally within past years (International Lesbian, Gay, Bisexual, Trans and Intersex Association, 2017;Smalley et al., 2018), equality in healthcare for all SGM youth groups has still not achieved; for example, the healthcare of transgender youth is still missing evidence-base (World Medical Association 2015;de Vries et al., 2016). Recently, World Health Organization removed transgender identity from the category of 'mental, behavioural and neurodevelopmental disorders' to 'conditions related to sexual health' in the International Classification of Diseases (ICD11) list (World Health Organization 2018b). This shows an improvement in understanding gender diversity. However, significant work is still needed to ensure that healthcare and medical guidelines take a step to pro-trans direction in practice, and this promotes recognising the needs of transgender youth in particular.
This review showed significant issues related to transgender youth care. First, two studies defined transgender as a sexual orientation (Ginsburg et al., 2002;Snyder et al., 2016), thus differing from the definition of trans as a gender identity in the literature (Smalley et al., 2018). This indicates that the understanding of gender identities may not be congruent in research yet. Second, although Vance et al. (2015), Torres et al. (2015), Lefkowitz and Mannell (2017), and Shires et al. (2017) studied transgender youth healthcare from health professionals' perspectives, no studies focussed on transgender youths' perceptions about healthcare. Third, several studies on SGM youths' perspectives included transgender youth in their study (Ginsburg et al., 2002;Hoffman et al., 2009;Fuzzell et al., 2016;Snyder et al., 2016) by grouping them together with sexual minority youth. However, grouping transgender youth and sexual minority youth together may cause prioritising sexuality over gender issues in studies (Steinke et al., 2017). Transgender youth have some unique aspects in healthcare such as hormone treatments, gender dysphoria, right to define their gender to their medical files (World Professional Association for Transgender Health, 2011); therefore, the results in this review cannot be generalised to transgender youths' healthcare. Other gender minority youth were rarely included in the studies, and this showed a significant research gap about gender diversity among young people. There is a need for research focussing on the perspectives of transgender and other gender minority youth in healthcare and how gender norms are affected in healthcare (Steinke et al., 2017). Furthermore, the results showed health professionals lacked knowledge about the health issues of transgender youth (Torres et al., 2015;Fuzzell et al., 2016;Shires et al., 2017). More attention in research should consider how health professionals' knowledge gaps can be diminished.
The review has several practical implications. First, the results show health professionals need education about SGM youth, and the results can be used as a theoretical framework for education about diversity-affirming care. Second, health professionals can use the results in their practice when they want to be inclusive for SGM youth, for example through neutral language and not making assumptions from their patients' gender and sexuality. Third, when healthcare policies and practices are developed into diversity-affirming, the results give examples of elements for creating inclusive healthcare settings and information for SGM youth.

Limitations
Some limitations are worth noting in this review. First, the literature search used six databases, but only 18 research articles were found to be eligible for this review. However, the literature search was planned and performed carefully. Two authors did the search systematically by following the same search strategy, and they screened and selected research articles in cooperation. Second, the wide range of research methods used in the studies may affect the analysis and results of this review. This review aimed to describe the role of heteronormativity with a broad approach and not be limited by studies with a specific research method. Furthermore, the quality appraisal of the studies was done by two authors to get an overview of the differences between studies in their quality. Third, the quality appraisal showed that several studies in this review were low in quality, thus we recommend the results are considered with a carefulness. This review was,  however, describing heteronormativity for the first time with a broad approach, and the exclusion of studies with low quality was considered incongruent with this. Finally, as one inclusion criterion was English language, the review may have missed eligible studies published in other languages.

Summary
The results of this review provide a new understanding about the encounters between SGM youth and health professionals in healthcare. This understanding addresses how heteronormativity is related to these encounters and how an open-minded encounter is possible for SGM youth by giving them enough space to be diverse and support for their needs. Further research is needed about the role of heteronormativity in healthcare and the application of diversity-affirming care into healthcare practices. In addition, transgender and other gender minority youths' voices need to be heard in research. With further research, health professionals may be able to develop their skills when encountering SGM youth without the influence of heteronormativity, give information and support that are relevant to them, and adequately understand how diversity in sexuality and gender is encountered with young patients.