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Risks associated with unintended pregnancy include unsafe abortions, poor maternal health-seeking behaviour, poor mental health, and potentially, maternal and infant deaths. Adolescent girls with unintended pregnancies are particularly vulnerable as they are at higher risk of eclampsia, premature onset of labour, and increased neonatal morbidity and mortality. Unintended pregnancy, with the right combination of interventions, can be avoided. Evidence-based decision-making and the need for a robust appraisal of the evidence have resulted in many systematic reviews. This review of systematic reviews focuses on adolescent pregnancy prevention and will seek to facilitate evidence-based decision-making. Two review authors independently extracted data and assessed the methodological quality of each review according to the AMSTAR 2 criteria. We identified three systematic reviews from low- and middle-income countries and high-income counties and included all socioeconomic groups. We used vote counting and individual narrative review summaries to present the results. Overall, skill-building, peer-led and abstinence programmes were generally effective. Interventions focused on information only, counselling and interactive sessions provided mixed results.
In contrast, exposure to parenting and delaying sexual debut interventions were generally ineffective. Adolescent pregnancy prevention interventions that deploy school-based primary prevention strategies, i.e. strategies that prevent unintended pregnancies in the first place, may effectively reduce teenage pregnancy rates, improve contraceptive use, attitudes and knowledge, and delay sexual debut. However, the included studies have methodological issues, and our ability to generalise the result is limited.
Sub-Saharan Africa’s (sSA) adolescent population (aged 10–19) is growing [8]. Child mortality on the continent is declining faster than fertility, which has increased the relative proportion of the adolescent population [44]. Consequently, many countries enter a new demographic era that allows them to leverage this youthful population to ensure a favourable population structure for social and economic gains [13]. For countries to reap these social and economic benefits, targeted investments in adolescents’ health, education, and well-being must be sustained. However, as of 2019, adolescents aged 15–19 years in low- and middle-income countries (LMICs) experienced an estimated 21 million unintended pregnancies per year, resulting in an estimated 12 million births [21], Sully et al. [67]. Over half (55%) of the unintended pregnancies among 15–19-year-old adolescent girls result in abortions, which are frequently unsafe in LMICs [77].
The potential consequences of unintended adolescent pregnancies are well known. They include adverse developmental, economic and health outcomes such as child undernutrition, increased risk of school dropout rates and decreased educational attainment [24, 74]. Adolescents are more likely to be discriminated against when seeking information and services related to sexual and reproductive health because they may feel embarrassed or encounter judgmental providers and be stigmatised [10, 62]. In contexts where contraceptive and abortion services are unavailable, difficult to access or illegal, this can result in women opting for and receiving sub-standard or unsafe services. These risks are heightened for adolescent girls and can lead to long-term adverse health impacts and death [20].
Early childbearing is also associated with risks for adolescent girls who continue the pregnancy. Compared to older mothers, adolescent mothers are far more likely to deliver prematurely, suffer complications during labour, and give birth to a low-birth-weight baby [6]. Moreover, children born to adolescent mothers are far more likely to be stunted, wasted or underweight [74].
Pregnant adolescents and adolescent mothers drop out of school at much higher rates than their non-pregnant peers, even in countries with policies encouraging pregnant adolescents to remain in education [66]. A lack of education limits girls’ economic and social opportunities, increasing their dependency on others and, in turn, their vulnerability. Adolescent pregnancy is a public health problem. Sustainable Development Goal (SDG) 3.7.2, which focuses on the adolescent birth rate, acknowledges this and tasks the global community to address this issue. In sSA, approximately one in five teenage girls become pregnant [35]. While the overall trends in adolescent birth rates show a decline globally, the sSA region continues to exhibit a significant lag [71].
The COVID-19 pandemic has exacerbated this public health problem by interrupting access to essential health services [35]. In addition to health services being interrupted, other essential services, such as schools, were also affected. There is an evidence base for the protective effect schooling has on adolescent girls, as it decreases their likelihood of becoming a child bride and falling pregnant [1, 40, 56]. Access to adolescent-friendly sexual and reproductive health services is critical for girls who find themselves pregnant. Despite this, many girls have been unable to attend school and access sexual and reproductive health services due to national lockdowns and severe restrictions on movement, significantly increasing their chances of getting pregnant [40]. As national governments seek not only to address the virus but also the consequences of the virus, such as an increase in child marriages, school dropouts and pregnancy, policymakers want to understand better what interventions work and how applicable these interventions are to their context [46, 79].
Unintended pregnancy is defined as a pregnancy that is either unwanted, such as a pregnancy that occurs when no children are desired, or a pregnancy that is mistimed, such as pregnancies that occur earlier than desired [61]. Approximately 40% of all global pregnancies are unintended, and a quarter occur in sub-Saharan Africa [7]. The issue is particularly acute among adolescent girls, with at least 12 million 15–19-year-old girls in the developing world dealing with unintended pregnancy [21]. Unintended pregnancies tend to occur when adolescent girls or their partners do not use family planning methods, use them incorrectly or inconsistently or are coerced into sex. Unintended pregnancy is not a static concept since pregnancy can start by being intended and then become unintended because of circumstances in which the adolescent finds herself. Many factors influence the different pathways that lead to an unintended pregnancy. This includes but is not limited to a lack of sexual and reproductive health (SRH) knowledge, access to adolescent-friendly SRH services and lack of resources to access services [78]. The inability to openly discuss and make contraceptive decisions has also been cited as a barrier for adolescent girls, particularly girls with older partners [35]. In certain situations, adolescent girls may be subjected to societal pressure to marry and have children once married. These situations or circumstances encompass social and peer pressures to engage in sexual activities, conceive, coercion exerted by familial influences, and limited autonomy concerning contraceptive selection and utilisation, contributing to adolescent pregnancy incidence [19]. However, it should also be noted that some adolescents intend and desire pregnancy and childbirth [25].
Unintended pregnancy is associated with an increased risk of unsafe abortions, poor maternal health-seeking behaviour, poor mental health and potential maternal and infant deaths [9, 34, 73]. A recent study compared children’s morality rates among first-time mothers aged
For this study, we define intervention(s) as any activities that target adolescents and are undertaken to prevent unintended pregnancies among adolescent girls. Pregnancies can be prevented by encouraging adolescents to delay their sexual debut, countering child marriage practices, increasing uptake and continued use of contraception, and educating girls and boys on the risks of unintended pregnancies [52]. Drawing from the literature on evidence-based guidelines for preventing adolescent pregnancies [68], we identify three pregnancy prevention strategies.
Primary prevention strategies: Include strategies that prevent unintended pregnancies in the first place. Examples are a supportive family environment, comprehensive sexuality education, contraception, and prevention and detection of sexual and gender-based violence.
Secondary management strategies: Early pregnancy diagnosis and counselling on pregnancy options, including access to safe abortion care.
Tertiary management strategies: Prevention of adverse events associated with unintended pregnancy, for example, treatment of incomplete abortion; access to services for psychosocial trauma; and services for antenatal care and maternity services to prevent maternal morbidity and mortality.
Communities that tend to be the most successful adopt a multifaceted approach, i.e. implement prevention programmes that operate at the primary, secondary and tertiary levels. These programmes seek to not only focus on sex and the potential consequence of engaging in unsafe sex but also address contextual factors such as social norms, empowerment, skill training and personal development. Moreover, the target group should not be limited to adolescent girls but also include adolescent boys, parents, teachers and community leaders [52]. For this review, we focus on primary prevention strategies. For example, school-based programmes delivered via the school platform mainly focus on psychosocial risk and protective factors that involve sexuality. These primary prevention strategies aim to improve adolescent girls’ and boys’ knowledge and awareness of their sexual reproductive health and reduce unintended pregnancies [69].
Leveraging the school platform to deliver interventions helps ensure that students have a safe space to learn about their sexuality, pregnancy prevention and the transmission of sexually transmitted diseases, and where to access SRH services. Moreover, school-based programmes allow adolescents to engage with these topics in a socially acceptable forum. Delivering sex education via schools ensures that more adolescents are reached before their sexual debut [41].
Although clinic and community-based (i.e., establishing health clubs to educate on SRH and facilitate referrals to clinics, mobile health clinics for youth and SRH services within youth centres) tend to incorporate elements of educational programmes, unlike school-based interventions, these sessions can also be delivered separately as a stand-alone intervention both within the clinic or outside on the broader community, to include out of school adolescents. These interventions also promote access to family planning services for adolescents, improve adolescents’ knowledge of methods and dispel misconceptions [59]. Community contraceptive-promoting activities can also seek to shift social norms within the community that inhibit the uptake of methods, which also facilitates the acceptability of sex educational programmes at school, the creation of adolescent-friendly services and the promotion and distribution of methods [59].
Youth development interventions not only focus on the sexual health needs of the target population but also address these needs within a programme that tries to tackle other cross-cutting issues through skill building and mentorship. The success of these programmes is contingent upon the involvement of various stakeholders such as schools, religious groups, the community, health officials and adolescents. In addition, implementors must ensure the intervention is practical, culturally apt and evidence-based [52].
Evidence-based decision-making and the need for a robust appraisal of the evidence have resulted in many systematic reviews. Systematic reviews are a valuable tool for summarising a large body of evidence, and this is reflected in the statistics that approximately 22 new systematic reviews are published daily [29]. However, a large number of systematic reviews leads policymakers and other decision-makers to find themselves unable to call upon a single document that robustly apprises the current state of the evidence. Currently, many systematic reviews focus on adolescent pregnancy prevention. A decision-maker who wants to understand better what interventions they can implement to curb adolescent pregnancy rates would have to review multiple systematic reviews. A systematic review like this one aims to focus more broadly on an outcome, such as unintended adolescent pregnancy, and identify potentially effective interventions [4]. Thus, this review of systematic reviews focuses on unintentional adolescent pregnancy prevention and will seek to facilitate evidence-based decision-making.
To synthesise systematic reviews on interventions to prevent unintended adolescent pregnancy.