The findings are in accordance with studies conducted in developed countries, such as the U.S.A. and U.K., showing that pubescent youth are susceptible to poor mental health outcomes because of the dearth of accessible adolescent-friendly health services and restrictions to access to appropriate and accurate knowledge, particularly for unmarried females [50]. Researchers who have conducted studies in LMICs have suggested that the stigma attached to adolescent sexual behavior, unintended pregnancy, early childbearing, abortion, and STIs can result in risky and unsafe behaviors, and unfavorable health and social outcomes. This includes shame, social marginalization, violence, and mental health illness, which further restrict access to sexual health services [51,52]. These findings are parallel to the findings of our review.

The results of this scoping review draw attention to several aspects of sexual health, including privacy, confidentiality, health care services, and sociocultural norms. Sexuality is a sensitive issue in any culture, and the norms that regulate sexual behavior vary from one geographical area to another, from one subculture to another, and even from one age group to another [47]. The lack of open discussion of sexual matters with parents, teachers, and friends because of embarrassment, fear, shame, stigma, and conservative socio-cultural and religious norms contribute to adolescents’ inadequate knowledge and skills to manage sexual health issues [53]. For example, we found that menstruation is usually associated with religious and cultural beliefs in Asian and African cultures [36,37], which may create challenges in accessing appropriate health care services and speaking openly about menstruation. The perpetuation of the cultural perspective that menstruation is ‘dirty’ and that it must be hidden and should not be discussed in mixed company deprives adolescent girls of the opportunity for more information to take control of their sexual health and ensure their psychological well-being. However, studies conducted in four African countries in Burkina Faso, Ghana, Malawi and Uganda have shown that age-appropriate and informed discussions on sexuality between parents and adolescents make the youth in the community more sexually healthy [54,55].

The issue of confidentiality with regard to adolescent sexuality involves careful consideration of how to address adolescents, for example, to ensure the protection of their integrity and respect existing societal values and subculture values [56]. In our review, we found that adolescent girls and boys do not always consider health care professionals as sources of support or unbiased advice and, in fact, consider them judgmental and disrespectful. Moreover, studies examining attitudes of healthcare providers towards contraceptives for unmarried adolescents and factors affecting the adequate provision of these services to adolescents in Nigeria and Cape Town, South Africa corroborate these findings [57,58].

In accordance with our findings, previous evidence from LMICs also demonstrates that sexual and reproductive health services that target adolescents are extremely disjointed, poorly synchronized, and low in quality [5,59,60]. Additionally, our findings are similar to those of previous reports showing that health care professionals face numerous challenges in providing care to adolescents, because they need specialized skills and knowledge for consultation, interpersonal communication, and interdisciplinary care [11]. This finding is understandable in view of previous studies that emphasized that the attitudes of health care professionals need to change to enable adolescents to seek help from qualified health care providers for safe sexual health practices [60,61]. We also found that training and educating professionals, developing stakeholder interrelationships, and using evaluative and iterative strategies are frequently recommended strategies to introduce and promote change in adolescents’ sexual health practices, which is similar to the findings of other studies conducted in Asian and African context [11].

In the sociocultural context of LMICs, sexuality is considered the privilege of older and married individuals, which makes it extremely difficult for young people to access sexual health counseling [62]. Other studies have supported these findings and shown that the stigma of risky sexual behaviors and STIs, including HIV and AIDS, further restrict the access of those who are stigmatized to sexual health services. Families, communities, and the healthcare system can be agents of stigmatization through such behaviors as abusing, insulting, and deserting adolescents [63,64]. Consequently, young people might use withdrawal as a coping strategy in the face of perceived or experienced stigma. This could also explain the finding of a strong association between adolescent girls’ and boys’ feelings of loneliness and their failure to seek sexual health care when they need it.

The concern about the confidentiality of adolescents’ personal information is a substantial hurdle to access to sexual healthcare services. A study conducted in Tanzania with young people has shown that adolescents may have a profound fear that their parents will learn about their accessing sexual health services [65]. In agreement with our findings, previous researchers have shown that adolescents are concerned that family, friends, or other community people who are acquainted with their parents will recognize them in the waiting room. They might also worry that healthcare providers who have social connections with their parent(s) or guardian(s) might purposefully or unintentionally reveal confidential information [66]. Alford found that, if her adolescent participants’ healthcare professionals notified their parents, 83% would discontinue access to sexual health services, whereas only 1% would abstain from sex [67].

Adolescent girls and boys often require guidance in making decisions, especially in dealing with sexuality issues. Biddlecom et al. and Namisi et al. offered insight on the importance of sexuality education and recommended that adolescents should receive essential information and learn skills through comprehensive sexual and reproductive health education to prevent mental health problems [54,55]. Biddlecom et al. and Namisi et al. also suggested that age-appropriate and informed discussions on sexuality between parents and adolescents improve the sexual health of youth in the community [54,55]. However, more work is needed in LMICs to ensure that adolescents receive accurate education on sexuality to understand how to practice healthy sexual behaviors eventually.

Our review revealed that the persistent inequality among adolescent girls and boys and restrictive gender norms can be translated into a range of negative mental health outcomes, especially for young girls. These findings are understandable in view of the work of Blum, Mmari, and Moreau in their study in 15 different countries of children aged 10–14 years, they found that boys are constantly encouraged to be strong and autonomous, whereas girls are considered vulnerable and in need of protection. Moreover, with the onset of puberty, boys are expected to prove their toughness and sexual ability, and girls are responsible for attracting male attention [68].

In addition, their peers persecute and mock boys who do not achieve local masculinity standards, but girls who transgress the social norms of sexual propriety are shamed and humiliated [68,69]. Concerns about female sexuality and reputational risk cause parents to tightly control their daughters’ behavior and freedom of movement, which can affect their psychological well-being.

Sexuality embraces so much more than just the physical act and has both physical and psychosocial components (East & Hutchinson, 2013; Hensel, Nance, & Fortenberry, 2016). The ways in which individuals express their sexuality depend on a range of factors, such as culture, religion, society, economics, politics, law, history, and spirituality [8,22].

The current agenda for Sustainable Development 2030 recognizes the need for greater accountability, especially for the Global Strategy for Women’s, Children’s and Adolescents’ Health [70]. Our findings indicate a paucity of research regarding the association between sexuality-related stressors and mental health among adolescent populations. Most of the research that is available has focused on girls, and there is a major gap in knowledge on the experiences of boys. This implies an urgent need for comprehensive research on the relationship between emerging sexuality and mental health in adolescents.