Interventions and Strategies to Improve Sexual and Reproductive Health Outcomes among Adolescents Living in Low- and Middle-Income Countries: A Systematic Review and Meta-Analysis

: Adolescent access to quality sexual and reproductive health and rights has been a major issue in most low- to middle-income countries (LMICs). This systematic review aims to identify the relevant community and school-based interventions that can be implemented in LMICs to promote adolescents’ sexual and reproductive health and rights. We identiﬁed 54 studies, and our review ﬁndings suggested that educational interventions, ﬁnancial incentives, and comprehensive postabortion family planning services were effective in increasing their knowledge and use of Adolescent Sexual and Reproductive Health and Rights (ASRHR) services, such as contraception, which led to a decrease in unwanted pregnancies. However, we found inconclusive and limited evidence on the effectiveness of interventions for improved violence prevention and adolescent behavior towards safe sexual practices. More rigorous studies with long-term follow-ups are needed to assess the effectiveness of such interventions.


Background
Adolescence is a critical period during which young people experience extensive biological, psychological, and social changes [1].Sexual and reproductive health (SRH) and access to SRH services are basic human rights, and based on sustainable development goals (SDG) (target 3.7), universal access to SRH services should be attained by 2030.However, SRH knowledge and service remains limited to many in low-to middle-income countries (LMICs) [2], home to 90% of the world's approximately 1.2 billion people aged 10-19 [3][4][5].
Adolescent Sexual and Reproductive Health and Rights (ASRHR) are distinct from those of adults, and the neglect of a specific ASRHR can affect an adolescent's physical and mental health, future employment, economic well-being, and the ability to reach his or her full potential [6,7].Despite efforts to improve the uptake of SRH knowledge and services, unmet SRH needs remain high and are particularly dire for young people living in LMICs.There is also a substantial lack of research on the effectiveness and scaling-up of community-based interventions focused on improving SRH among young people in specific cultural contexts.Further research is needed to better understand which SRH interventions have demonstrated effectiveness for improving SRH in LMICs to increase evidence-based practices and inform decisions to invest in scaling-up of effective interventions.
Presently, adolescents living in LMICs suffer disproportionately from undesirable SRH outcomes, such as early or unintended pregnancy, unsafe abortions, sexual violence, and sexually transmitted infections (STIs), including HIV [7,8].Young women, particularly adolescent girls, from LMICs are particularly vulnerable to poor SRH.Almost half of women aged 20-24 in Asia and Africa are married by the age of 18, which puts them at a higher risk for early pregnancy, maternal and child disability, and mortality [9,10].The environment in which adolescents are making decisions related to their SRH is also rapidly evolving.Rates of initial sexual activity during early young age are growing in many LMICs [11,12], and childbearing and marriage are increasingly unlinked [13].In many countries, a high prevalence of HIV increases the risks associated with early sexual activity [14,15].For example, in many countries in Sub-Saharan Africa, HIV/AIDS is a generalized epidemic, and young people account for almost two-thirds of people living with HIV [16].Therefore, developing, implementing, and evaluating interventions that can facilitate the development of healthy sexual behavior and relationships among adolescents is a priority.Community and school-based programs appear to be a logical choice for SRH education since most young children attain at least some education [17,18], particularly with the international recognition of the importance of schooling.In addition, studies have also reported that community-based interventions aimed at providing SRHR information and services can help to reduce ASRHR health challenges associated with adolescent pregnancies and marriages [19][20][21].
A growing body of evidence emphasized the scaling up and sustainable implementation of ASRHR community-based health interventions to strengthen ASRHR [22][23][24][25][26][27][28].However, many questions remain about what interventions work and which interventions can be sustainable and potentially scalable.No existing systematic review has examined the evidence for the effects of community and school-based interventions across multiple areas of ASRHR in LMICs.To address this gap, we conducted a systematic review to assess the range and nature of community and school-based interventions implemented to improve the SRH of adolescents in LMICs.The findings will aid in the development of a research program to better meet the SRH needs of this population.The further objectives of this review are to identify and evaluate the effectiveness of different interventions employed to improve ASRHR in LMICs, understand the approaches and strategies in successful delivery of ASRHR intervention, and identify knowledge gaps in those contexts.

Methods
This systematic review has been registered with the International Prospective Register of Systematic Reviews (PROSPERO) database under ID number CRD42019136323 and follows the recommendations established by the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) [29].
A systematic literature search was conducted on 11 April 2020, and re-updated in April 2021 using MEDLINE, EMBASE, PsychINFO (Psychological Abstracts), Ovid Global Health, CINAHL (Cumulative Index to Nursing and Allied Health Literature), the Cochrane Central Register of Controlled Trials, ProQuest Sociological Abstracts, ProQuest Dissertations, and Theses Global, Scopus, Web of Science, Centre for Reviews and Dissemination Databases, and the WHO library and other relevant websites (that publish ASRHR material).To avoid publication bias, we searched grey literature, the bibliographies of all relevant papers, and conference proceedings.We contacted experts in the field to identify any missing papers or programs.(Sexual and Reproductive Health, adolescents, low-and middle-income countries, and study design).The full search strategy and terms used are available in Supplementary File S1.No language restrictions were applied; however, only papers published after 1990 were included as the adolescent SRH agenda was formally started at that time.
We included all randomized controlled trials (RCTs), quasi-RCTs, and controlled before-after (CBA) studies on adolescents aged 10-19 living in low-and middle-income countries (LMICs) as defined by the World Bank [30].Studies were included if they delivered interventions to improve SRH such as delaying early and forced marriage; improving or promoting family planning, contraception and the spacing of pregnancy; providing access to safe abortion; preventing and treating HIV/AIDS and other STIs; addressing intimate partner and sexual violence; menstruation and feminine hygiene; or any other indirect interventions such as education, economic development, and empowerment.We included studies that compared these interventions with no intervention or standard interventions.We also included studies at a cross-cutting age when data on adolescents was reported separately.We excluded studies with no control arm, and those conducted in high-income countries.
Primary outcomes of interest were unintended pregnancies, rate of abortion, use of family planning methods, teenage pregnancy, repeated teenage pregnancy, the incidence of STI/HIV, and rates of unprotected sex.Secondary outcomes of interest were knowledge related to ASRHR, use of ASRHR services, quality of life measured using any scale; and maternal/child morbidity and mortality.
Two reviewers (MR and SA) independently screened the titles and abstracts for eligibility.After the initial search, full texts of relevant articles were examined for inclusion and exclusion criteria.Primary studies that fulfilled the inclusion criteria were selected for this systematic review.Any disagreement among the authors was resolved through consensus or consulting a senior reviewer (SM).Two authors (MR and SA) extracted relevant information independently from the studies.The following items were extracted from each study if available: author's name, study design, country, target population, intervention, and study outcome.The methodological quality of included RCTs was assessed using the Cochrane risk of bias tool [31] and q-RCTs were assessed using EPOC criteria [32].Two reviewers (SM, SA) independently assessed the quality of the studies.Disagreements between reviewers were resolved by consensus or by the decision of a third independent reviewer (ZL).
Data were entered and analyzed using Review Manager (RevMan) version 5.4.A mean difference (MD) with a 95% confidence intervals (CI) was used for continuous data and relative risk (RR) with 95% CI was used for dichotomous data.Heterogeneity between the studies was explored using the p-value of Chi 2 and I 2 .Fixed-effect models were used, but when the outcomes were heterogenous, random effect models were used.Subgroup analysis was performed based on the type of strategies employed (school-based interventions, community-based intervention, or a combination of these or other interventions) and the type of study design used.

Study Characteristics
The search strategy identified 5715 articles.After removing 122 duplicates, 5593 were screened on title abstracts and 679 were retrieved for full texts.Based on the final inclusion criteria, 54 articles were included in our systematic review.Studies excluded after full-text screening are mentioned in the PRISMA flow diagram (Figure 1).Of the 54 included studies, 12 were quasi-RCTs and 42 were RCTs.Three studies were entirely conducted on young people aged 10-24 (n = 5929), whereas the remaining 51 studies were conducted either with adolescents aged 10-19 (n = 69,553) or youth aged 15-24 (n = 19,348).Regarding geographical distribution, 38 studies were conducted in Africa [24,, 9 in Asia [70][71][72][73][74][75][76][77][78], and 7 in North America (the Caribbean) [79][80][81][82][83][84][85].Of the 54 studies, 39 were meta-analyzed; however, 15 could not be pooled because either they did not report the outcome of interest or reported it differently.Table 1 presents the characteristics of the studies.The methodological qualities are provided in Figure 2. Studies were not excluded based on assessment scores as the purpose was to examine and gain insight into the rigor of existing research.(Table 2 presents the findings from the meta-analysis discussed in the sections below).• Prevalence of HIV 2; 3643 1.12 (0.79, 1.57) (p = 0.94); I 2 = 0%

Summary of Adolescent Sexual and Reproductive Health and Rights (ASRHR) Interventions
Of the 54 studies, 48 studies focused on interventions related to ASRHR education, and of these, 33 were conducted in Africa [24,; 8 in Asia [70][71][72][73][74][75][76][77]; and 7 in North America (the Caribbean) [79][80][81][82][83][84][85].These studies implemented ASRHR educational interventions in school and community settings in the form of community-based education programs, school and community-based peer education programs, sports-based interventions, internet-based programs, or a combination of the above (i.e., multicomponent interventions).Another three studies conducted in Africa, including Kenya [34,40,65]; and Zimbabwe (n = 1) [67], implemented interventions that focused on providing comprehensive school support packages to adolescents.These packages included uniforms, tuition fees, and helpers to school-going students.While the remaining three studies assessed a number of cross-cutting ASRHR interventions: one study focused on the provision of comprehensive post-abortion family planning service packages to young women in China (n = 1) [78]; another focused on evaluating the effect of financial incentives to caregivers to have adolescents undergo HIV testing and counseling services in Harare, Zimbabwe, (n = 1) [68]; and the third focused on addressing menstrual health and hygiene by providing menstrual products to school-going adolescents in rural western Kenya (n = 1) [69] (See Table 2).
Subgroup analysis based on the type of ASRHR educational interventions revealed that sports-based interventions in schools, community-based peer-group interventions, and multicomponent interventions were effective in improving knowledge of ASRHR (Figure 4).The multicomponent interventions included a range of interventions that aimed to increase ASRHR knowledge to adolescents via mass media campaigns, peer education, and targeted condom distribution in communities.Whereas interventions including counseling based on cognitive behavioral therapy, school-based programs, and communication campaign interventions were effective in improving the use ASRHR services, contraceptive methods, and condom use.The communication campaign incorporated various wide-distribution strategies to reach out to different audiences and reinforce ASRHR messages: posters in the community with key messages around sexual responsibility, peer pressure, AIDS, drugs, and alcohol; five different leaflets on saying "no" to sex, postponing sex, delaying parenthood, and STIs; newsletters by peer educators and schools on reproductive health issues.The campaign also entailed peer education, the launch and implementation of radio campaigns, community theatre and events, and a hotline to provide ASRHR support (Table 2).It is significant to note that ASRHR education interventions like Internet-based programs and text messaging (unidirectional or interactive) were not found effective for improving ASRHR outcomes related to family planning (Internet-based programs RR 1.01; 95% CI 0.90 to 1.13; n = 1 study); or pregnancy rates (via unidirectional text messaging RR 0.57; 95% CI 0.17 to 1.93, n = 1 study; via interactive text messaging intervention RR 0.86; 95% CI 0.27 to 2.75; n = 1 study).Similarly, community-based behavioral interventions with teenage girls and community-based interventions that included group sessions and the provision of health and legal services were not found effective in decreasing the rates of violence among adolescents (RR 1.10; 95% CI 1.01 to 1.19; n = 4 studies) (Table 2; Supplementary File S2; Figures S1-S3).

Provision of Financial Incentives to Improve the Uptake of HIV Testing and Counseling Services
One study conducted in Harare, Zimbabwe, examined the effect of providing fixed or lottery-based financial incentives to caregivers of children and adolescents for them to seek HIV testing and counseling services [68].Findings from the meta-analysis revealed them to be significantly effective (fixed incentive RR 2.43; 95% CI 1.86 to 3.17, and lottery-based incentive RR 2.04; 95% CI 1.54 to 2.69) (Table 2).

Comprehensive Post-Abortion Family Planning Services
We identified one study that found significant intervention effects related to family planning.Zhu et al. [78] examined the impact of providing comprehensive post-abortion family planning service packages to young women in three different cities in China.These included training of abortion service providers, group education and individual counseling of women on contraception, male involvement in education and counseling sessions, and referral of women to family planning services.Interestingly, our meta-analysis of this intervention revealed significant improvement in the use of any contraceptive method (RR 1.01; 95% CI 0.98 to 1.03); condom use (RR 1.97; 95% CI 1.45 to 2.66); unwanted pregnancies (RR 0.33; 95% CI 0.17 to 0.72); and induced abortions (RR 0.36; 95% CI 0.15 to 0.87) (Table 2).

Comprehensive School Support to Adolescents in Schools
Hallfors et al. examined the effect of providing comprehensive school support to school-going adolescents on rates of teenage pregnancy in Zimbabwe [67].The school support package included tuition fees, uniforms, and helpers.However, the meta-analysis indicated that the intervention was not effective in reducing teenage pregnancy rates (RR 0.16; 95% CI 0.01 to 3.26) (Table 2).

Provision of Menstrual Products to the School-Going Adolescents
The study in rural western Kenya conducted by Phillips-Howard et al. explored the effect of providing menstrual products (menstrual cups and pads) to in schools to decrease rates of STIs and Reproductive Tract infections (RTIs) [69].Findings from the analysis revealed that such interventions may not be effective (RR 0.79; 95% CI 0.34 to 1.79) (Table 2).

Discussion
Our systematic review aimed to evaluate the effectiveness of community and schoolbased ASRHR interventions in LMICs.The review also aimed to understand the approaches and strategies taken to successfully implement ASRHR interventions in these limitedresource settings.The findings suggest that ASRHR education (school and communitybased interventions, sports-based interventions, counseling based on cognitive behavioral therapy, multi-component interventions, and communication campaigns) are effective for improving young people's knowledge, attitudes, and practices toward ASRHR.The outcomes that were significantly improved through these interventions were the increased use of contraceptive methods, reduced sexual partners, adopting safe sexual behaviors, decreased rates of STIs and HIV, and the increased use of ASRHR services.On the other hand, technology-based ASRHR interventions were not found effective regarding protected sex and reducing unwanted pregnancies.Our findings are consistent with existing studies related to digital-based ASRHR interventions.A systematic review found statistically significant impacts mostly for the knowledge-based outcomes [86].However, these may not essentially translate into meaningful reductions in sexually risky behavior [86].Very limited RCTs or qRCTs studies were conducted to evaluate the effectiveness of digital or mHealth interventions, but more RCT studies are needed to understand the effectiveness, replicability, and scalability of new digital/mHealth-based ASRHR interventions in LMICs [87].
Our review also found that non-drug interventions such as providing financial incentives can be effective in improving the use of ASRHR services such as HIV testing and counseling services.This finding was consistent with another systematic review conducted by Wekesah et al., which evaluated non-drug interventions on maternal health [88].Costsharing programs between public and health care facilities and output-based approach (OBA) vouchers to cover the cost of certain maternal health services (antenatal visits and facility-based deliveries) have the potential to increase access to these services among the poor and reduce maternal mortality [88].Similarly, our findings also suggested that the use of contraception can be increased among sexually active young people through comprehensive post-abortion family planning services.Comprehensive training of abortion service providers and counseling of both partners on contraceptive methods can be effective for reducing unwanted pregnancy and unsafe abortion.Globally, comprehensive post-abortion family planning services have been endorsed as a high-impact practice in family planning services [89].Several studies found that providing family planning services as part of postabortion care can increase contraceptive use and reduce repeat abortions [89,90].
Interestingly, our review suggested that comprehensive school support programs (provision of tuition fees, uniforms, and helpers to adolescents) to decrease school dropout rates, are not effective for reducing teenage pregnancy.However, our findings are insignificant compared to the available evidence on the effectiveness of comprehensive school support programs.According to Ferre (as cited in a guidance document by UNFPA, 2015), the World Bank estimates that the risk of pregnancy declines every year when a young girl remains in school after age 11 [91].Moreover, a systematic literature review conducted to evaluate the influence of education on teenage pregnancy in low-income countries, suggests that teenage girls who remained longer in schools had delayed pregnancy longer than girls who had little or no education or had been out of school [92].Moreover, the study suggested that social workers should focus on interventions that ensure enrollment of girls in LMICs and provide opportunities to them to be able to attend school [92].Such interventions can facilitate decreasing the burden of teenage pregnancy [92].Similarly, our review suggested that the provision of free menstrual cups and sanitary pads in schools may not decrease the rates of STIs and RTIs.However, this finding is inconsistent with the available evidence attesting to their effectiveness.According to a scientific review conducted by Van Eijk et al., menstrual cups are safe for menstruation management [93].Furthermore, the review found that there was no increased risk of infection associated with their use.

Limitations
There are certain limitations to this study.We restricted our search strategy to RCTs, quasi-RCTs, and CBA studies as we aimed to gather evidence of those ASRHR interventions that were evaluated via rigorous scientific methods in LMICs settings.We also excluded those studies that were evaluated via pre-or post-test evaluation strategies.This eventually led to the exclusion of many studies such as on female genital mutilation/cutting and digital/mHealth interventions to improve ASRHR outcomes.Many of the evidence came from single studies.Heterogeneity was higher for most of outcomes that suggested more robust trials be conducted to overcome these.In addition, many studies failed to use allocation concealment, blinding, and randomization to optimize their outcomes.Hence, most were rated as low or moderate in methodological quality.Moreover, because we restricted our inclusion criteria to LMICs, the findings of this study cannot be generalized to high-income countries.

Conclusion
Given the urgent need to identify strategies to promote ASRHR, this systematic review provided a comprehensive summary of effective interventions that can be implemented to improve ARSHR in LMICs.This review also provided potentially useful insights for the adaptation of evidence-based interventions to prevent and control adverse ASRHR outcomes.Our review suggested that a range of comprehensive interventions targeting sexual health education, counseling, and consistent birth control promotion and provision have the potential to promote ASRHR and prevent and control the adverse outcomes.

Figure 1 .
Figure 1.PRISMA Flow diagram for interventions to improve Adolescent Sexual and Reproductive Health and Rights (Adapted from Moher et al. 2009).

Figure 3 .
Figure 3. Impact of Adolescent Sexual and Reproductive Health and Rights (ASRHR) information on adolescent attitudes towards SRHR.

Figure 4 .
Figure 4. Impact of Adolescent Sexual and Reproductive Health and Rights (ASRHR) information on condom use.

Table 1 .
Characteristics of included studies.