Determinants of adolescent pregnancy in East Africa: a systematic review and meta-analysis

¹Geneva Centre of Humanitarian Studies, University of Geneva, Switzerland, City of Geneva, ²University of Global Health Equity, Burera, Rwanda

^&Corresponding author
Sandra Isano, Geneva Centre of Humanitarian Studies, University of Geneva, Switzerland, City of Geneva

Introduction    

Adolescent pregnancy remains a critical global health issue, especially in low-income settings where its prevalence is alarmingly high [1]. Each year, approximately 21 million girls aged 15 to 19 in low-income countries become pregnant. Notably, nearly half of these pregnancies (49%) are unintended, with about 16 million resulting in childbirth and approximately 3.2 million ending in abortion [2,3]. Although there has been a global decline in adolescent birth rates, sub-Saharan Africa continues to face severe challenges, with over 100 births per 1,000 women in this age group [4]. This issue extends beyond individual health, representing a complex public health crisis with significant implications for socio-economic development and gender equality [5].

In some cultures, pregnancy is viewed positively as a blessing [6,7]. However, for adolescent girls, early pregnancy often results in severe and detrimental consequences. One of the most significant impacts is the disruption of education; many young mothers are compelled to leave school, which severely limits their future economic opportunities and perpetuates cycles of poverty. This interruption not only affects their immediate financial stability but also hinders their long-term career prospects [8]. Furthermore, early pregnancy introduces additional challenges, such as increased risk of unemployment. Research highlights that adolescent pregnancy often leads to joblessness due to both a lack of educational qualifications and the stigma associated with early motherhood [9].This combination of factors further restricts their ability to achieve economic independence and secure stable employment [10].

The adverse outcomes of adolescent pregnancy extend beyond the individual, significantly impacting the health and development of the child. Children born to adolescent mothers are at a higher risk for low birth weight, premature birth, and developmental delays [10]. These children often face additional challenges due to the mother's immaturity and potential instability in the mother-child relationship [11,12]. In some cases, these children are raised by grandparents or other relatives, which can result in frequent changes in caregivers [13]. This instability can increase the risk of neglect and negatively affect the child's overall development [13,14].

Adolescent pregnancy is a significant concern with varying social determinants across different regions of the world. Among the factors contributing to adolescent pregnancy are poverty, cultural and religious beliefs, early marriages, and limited access to education, among others. These factors interact in complex ways, but their impact can differ greatly depending on the socio-cultural and economic context of each region [9,11,15]. For example, in many parts of sub-Saharan Africa, traditional practices and religious beliefs significantly contribute to high rates of adolescent pregnancy. Early marriages and cultural norms are key factors influencing these rates [16,17]. In other regions, economic instability and limited access to comprehensive sexual education may be more prominent [18]. In Eastern Africa, the determinants of adolescent pregnancy are shaped by a unique combination of cultural practices, educational barriers, and economic conditions. Traditional beliefs and early marriage customs are prevalent, while access to education varies significantly. Poverty exacerbates these issues by restricting access to healthcare and sexual education [2,19,20].

Existing literature has identified the factors contributing to adolescent pregnancy in sub-Saharan Africa, highlighting its high prevalence. While recent reviews stress the need for targeted interventions, they often provide broad, generalized insights that may not adequately reflect the specific context of individual regions [3,4,21,22]. A systematic review focused specifically on East Africa is necessary to fill this gap. By examining the unique socio-cultural, economic, and environmental factors influencing adolescent pregnancy in East Africa, this review aims to generate a more nuanced understanding. Such insights are crucial for developing tailored interventions that more effectively address the challenges unique to adolescents in this region.

Methods     

Study design and search strategy: a systematic review and meta-analysis were conducted to estimate the pooled prevalence of adolescent pregnancy and assess associated socio-economic factors in East Africa. The review followed PRISMA 2020 guidelines and adhered to the Joanna Briggs Institute (JBI) methodology for systematic reviews [23-25]. A comprehensive search strategy was used to identify both published and unpublished literature. Records were retrieved from MEDLINE (n = 140), R Discovery (n = 62), Scite AI (n = 540), Elicit AI (n = 64), and Demographic and Health Survey (DHS) reports (n = 5), yielding a total of 811 records. Boolean operators (AND, OR) were used to combine search terms including "adolescent pregnancy," "teenage pregnancy," "East Africa," and "risk factors." Reference lists of included studies were screened to identify additional eligible sources.

Study selection and eligibility criteria: following deduplication, 277 records were removed, and 180 were excluded by automated filters. After screening 140 titles and abstracts, 113 records were excluded. Of 27 full-text articles assessed, 8 were excluded due to ineligible study designs or exposures. Nineteen studies were included in the final analysis.

Inclusion criteria: published in English (2013-2023); focused on adolescent girls aged 13-19 years in East Africa; reported prevalence or socio-economic risk factors for adolescent pregnancy and used observational study designs (cross-sectional, cohort, case-control) or DHS data

Exclusion criteria: focused on male adolescents or non-empirical studies; review articles or qualitative research and ineligible design or exposure focus.

Definition of adolescent pregnancy: adolescent pregnancy was defined as pregnancy occurring among girls aged 13-19 years. Studies reporting first births, current pregnancies, or proxy indicators from DHS reports were included.

Quality assessment and data extraction: the JBI critical appraisal checklist was used to assess methodological quality. Two reviewers independently extracted data using JBI SUMARI. Extracted data included author, year, study location, design, sample size, target population, outcomes, and key findings. Discrepancies were resolved by consensus.

Heterogeneity and publication bias: statistical heterogeneity was assessed using the I² statistic. Thresholds of 25%, 50%, and 75% were used to denote low, moderate, and high heterogeneity [26]. Egger's regression test was used to evaluate publication bias [27]. Where bias was detected (p < 0.05), the Duval and Tweedie trim-and-fill method was applied [28].

Data analysis and presentation: data were entered into Microsoft Excel, and meta-analysis was conducted using the Metafor package in R [29]. A random-effects model was used to account for heterogeneity across studies. Forest plot was used to present the pooled prevalence of adolescent pregnancy, while summary tables were used to report associations with key socio-economic factors such as employment status, education, and poverty, expressed as odds ratios (ORs) with corresponding 95% confidence intervals (CIs).

Results     

Study selection: out of 811 records identified, 19 studies met inclusion criteria and were included in the meta-analysis. The study selection process is outlined in Figure 1.

Characteristics of included studies: the 19 included studies were conducted between 2013 and 2023 across East African countries, including Uganda, Kenya, Tanzania, Rwanda, Burundi, Democratic Republic of Congo, and South Sudan. The majority were cross-sectional (n = 12), with cohort (n = 5) and case-control (n = 2) designs also represented. Adolescents aged 13-19 years were the primary population of interest. Key outcomes included the prevalence of adolescent pregnancy and associations with socio-economic variables. Full study details are provided in Table 1.

Prevalence of adolescent pregnancy in East Africa: the prevalence of adolescent pregnancy varied from 5.2% to 34.0% across studies. The lowest prevalence was reported in Rwanda (Rwanda DHS 2019-20: 5.2%, 95% CI: 4.5-5.9), and the highest in Tanzania (Moshi et al. 2023: 34.0%, 95% CI: 30.0-38.0). The overall pooled prevalence across all 19 studies was 23.6% (95% CI: 15.0-33.4), suggesting that nearly one in four adolescent girls in East Africa has experienced pregnancy. There was substantial heterogeneity among studies (I² = 99.8%), likely reflecting variation in geography, methodology, and populations. Figure 2 presents the pooled prevalence forest plot.

Socio-economic factors associated with adolescent pregnancy

Employment Status: four studies examined the relationship between employment and adolescent pregnancy. One Rwandan study reported a significant positive association (OR = 1.51; 95% CI: 1.03-2.64), while the remaining three showed non-significant findings. The pooled OR from the random-effects model indicated that employed adolescents had significantly lower odds of pregnancy (OR = 0.27; 95% CI: 0.03-0.50). No heterogeneity was detected (I² = 0%, p = 0.28) Table 2.

Education Level: six studies assessed education. One study (Okigbo et al. 2015) showed a protective effect (OR = 0.20; 95% CI: 0.09-0.45), while four others found significant associations linking lower education with higher pregnancy risk. One study showed a non-significant effect. The pooled estimate was not statistically significant (OR = 1.06; 95% CI: 0.15-1.97), with substantial heterogeneity (I² = 92.02%) Table 3.

Poverty: four studies evaluated poverty. One Kenyan study reported a protective effect (OR = 0.30; 95% CI: 0.10-0.90), while two Ugandan studies found significant positive associations (Chemutai et al., OR = 2.80; 95% CI: 1.09-7.17; Amongin et al. OR = 1.70; 95% CI: 1.25-2.32). One Rwandan study showed a non-significant result. The pooled analysis found no significant overall effect (OR = 0.11; 95% CI: −0.75 to 0.96), with moderate heterogeneity (I² = 82.8%, p = 0.005) Table 4.

Discussion     

The findings from this systematic review and meta-analysis provide an overview of the prevalence and socio-economic determinants of adolescent pregnancy in East Africa. The pooled prevalence of adolescent pregnancy ranged from 5.2% to 34.0%, with the highest rate observed in Tanzania and the lowest in Rwanda. These findings align with previous research, which has reported similarly high rates of adolescent pregnancy across sub-Saharan Africa. In some parts of the region, including Tanzania, Uganda, and Kenya, adolescent birth rates exceed 100 births per 1,000 women, highlighting the magnitude of the issue [16,18,19]. The relatively lower prevalence observed in Rwanda suggests that national policies and interventions may be having a measurable impact, though the overall burden across East Africa remains substantial [30].

Importantly, our findings underscore the significant role of socio-economic factors—including poverty, low educational attainment, and unemployment—in influencing adolescent pregnancy. Adolescents from poor households were found to be at a higher risk of early pregnancy. This is largely attributed to limited access to healthcare services, including contraception and sexual and reproductive health information, as well as the economic pressures that may lead to transactional sex or early marriage [18,31]. These dynamics are well documented in the broader literature, which consistently highlights how poverty exacerbates vulnerability by restricting adolescents´ access to protective resources and support systems [17-19].

Education also emerged as a key determinant of adolescent pregnancy. Our meta-analysis found that while the overall association between education and adolescent pregnancy was not statistically significant, individual studies revealed strong links between low educational attainment and increased risk of early pregnancy. This is consistent with prior research demonstrating that girls who stay in school, particularly through secondary education, are significantly less likely to become pregnant [32]. Schools not only serve as platforms for delivering reproductive health education but also help delay marriage and childbearing and empower girls to make informed decisions about their bodies and futures. Adolescents who drop out of school are more vulnerable to early pregnancy, which can further limit their access to employment and perpetuate cycles of poverty [18].

Unemployment, another important factor in our analysis, also showed a significant relationship with adolescent pregnancy. While only one of the included studies found a statistically significant association, the pooled effect indicated that unemployment increased the likelihood of adolescent pregnancy. This is supported by studies suggesting that limited economic opportunities for young women increase their vulnerability to early childbearing, particularly in contexts where early motherhood is socially normalised or economically incentivised [21]. In the absence of meaningful employment, adolescent girls may view motherhood as their only viable life path, reinforcing gender-based economic disparities and limiting their potential.

Moreover, poverty was revealed as a foundational factor influencing all other socio-economic variables. While our findings showed mixed associations between poverty and adolescent pregnancy—with some studies showing significant positive effects and others showing no effect—the broader literature identifies poverty as a root cause that shapes adolescent girls´ reproductive trajectories [16,33]. Poor adolescents are less likely to remain in school, access reproductive health services, or resist social pressures that encourage early sex and marriage. Interventions addressing adolescent pregnancy must therefore go beyond individual behaviour change and incorporate structural approaches, such as conditional cash transfers, social protection programs, and economic empowerment initiatives.

As highlighted in our findings, the evidence synthesised in this review is based on data extracted from the included primary studies summarised in Table 1 [34-50]. These studies provide the empirical foundation for the prevalence estimates and socio-economic determinants discussed above. By integrating data across these diverse sources, this review offers a comprehensive understanding of adolescent pregnancy in East Africa and underscores the need for context-specific interventions informed by local evidence.

Conclusion     

In summary, our review reinforces the complex interplay between education, employment, and poverty in shaping adolescent pregnancy outcomes in East Africa. While individual interventions can help, sustainable reductions in adolescent pregnancy require a multisectoral approach that addresses the broader social determinants of health. Future policy should prioritise expanding access to education, improving youth employment opportunities, and implementing poverty alleviation strategies, particularly for adolescent girls. Such an integrated strategy is crucial not only to reduce adolescent pregnancy but also to improve long-term health, educational, and economic outcomes for young women in the region.

Competing interests     

The authors declare no competing interests.

Authors' contributions     

Sandra Isano conceptualized the study. Sandra Isano, Karl Blanchet, and Theogene Uwizeyimana reviewed all the data, with Sandra Isano and Theogene Uwizeyimana leading the analysis and manuscript preparation. Karl Blanchet provided critical feedback and guidance throughout the manuscript review process. All authors have reviewed, read, and approved the final version of the manuscript.

Tables and figures     

Table 1: characteristics of included sources of evidence

Table 2: association between employment status and adolescent pregnancy

Table 3: association between education and adolescent pregnancy

Table 4: association between poverty and adolescent pregnancy

Figure 1: search results, study selection, and inclusion process

Figure 2: pooled prevalence of adolescent pregnancy in East Africa

References