Prevalence and associated factors of adolescent pregnancy among sexually active adolescent girls: Evidence from the Peruvian Demographic and Family Health Survey, 2015-2019

Introduction

The World Health Organization (WHO) defines adolescents as those between 10 and 19 years of age.¹ Adolescence is a period of progression towards adulthood, necessary to reach physical, sexual, mental and social maturity.² However, it is during middle and late adolescence (15-19 years) when there is a greater development of responsibility for decisions and a greater search for autonomy.³ Therefore, the culmination of this period together with pregnancy can lead to various difficulties for the adolescent and the infant,⁴ with delayed prenatal care and a greater number of obstetric and perinatal complications⁵ being common, as well as a higher incidence of maternal mortality.⁶

According to the WHO, 12 million women aged 15-19 years and, approximately, 1 million girls under the age of 15 give birth each year.⁷ Latin America and the Caribbean have the second highest adolescent fertility rate in the world. Although this rate decreased from 65.6% (2010-2015) to 60.7% (2015-2020), there are still significant variations between sub regions and countries.⁸ In Peru, the Demographic and Family Health Survey (ENDES, for its Spanish acronym) revealed that the percentage of adolescents aged 15 to 19 years who were already mothers or were pregnant for the first time did not decrease notably and was maintained during 2014 to 2019 (prevalence of 14.6% and 12.6%, respectively).⁹ This issue of teenage pregnancy has been observed at a higher proportion in women with low educational levels, who reside in rural areas, belong to low socioeconomic strata and according to ethnicity.^10–12

Although in Peru, different factors associated with teenage pregnancy have also been reported in small studies or in gray literature,^13,14 it is not known which factors are associated with pregnancy during middle and late adolescence, which are the groups in which teenage pregnancy is most prevalent. In addition, there is no evidence in the literature on the factors associated with teenage pregnancy, taking as the baseline population those adolescents who initiated sexual relations, which could overestimate the effects found in other studies.^10–12 Therefore, the aim of the present study was to estimate the proportion and factors associated with pregnancy in adolescents aged 15 to 19 years who initiated their sexual life. The identification of associated factors with adolescent pregnancy could be an input for the strengthening of policies on reproductive education and prenatal care.

Methods

Population, sample and sampling

The ENDES is a survey with annual representativeness at the national, urban-rural level, by geographic domain and for the 25 departments of Peru. The sampling design of ENDES is two-stage, probabilistic by clusters and stratified at the departmental level and by urban and rural area. The primary sampling unit was made up of the selected clusters. The secondary sampling unit was made up of the selected homes.¹⁵

A total of 24 419 adolescent women aged 15-19 years were surveyed during the period 2015-2019, the effective sample for the analysis was composed of 6892 women who were those who responded to the dependent variable of interest (currently pregnant or who are mothers) and who reported having initiated sexual intercourse (Figure 1). Additional information on the ENDES survey methodology is available from Technical Report.¹⁵

Figure 1. Flow chart of selection of the study sample.

ENDES (Spanish acronym), Demographic and Family Health Survey.

Results

From a total of 24 419 adolescent women aged 15 to 19 years during the study period, 14 552 were excluded because they were not at risk of becoming pregnant (no history of sexual intercourse) and 2975 were excluded because they had variables with missing data, resulting in a final study population of 6892 (Figure 1).

The highest percentage of the study population corresponded to late adolescence (17 to 19 years) (83.2%), adolescents without a partner (67.9%), those with secondary or higher education (92.0%), those belonging to the second wealth quintile (23.1%), those currently in an occupation (58.0%), and those belonging to the mestizo ethnic group (37.8%), to the coast region (63.7%) and to an urban area (78.9%) (Table 1).

The prevalence of pregnancy among adolescents aged 15 to 19 years who initiated sexual relations was 30.1%, with a higher proportion among adolescents aged between 17 to 19 years (32.0; p<0.001), those with primary education or lower (64.8%; p<0.001), those with a partner (73.3%; p<0.001), those who belonged to the first wealth quintile (54.8%; p<0.001), those who did not work (35.0%; p<0.001), those who were not studying (51.5%; p<0.001), those who belonged to the jungle region (41.5%; p<0.001), as well as those from rural areas (55.4%; p<0.001) (Table 2).

Furthermore, the prevalence of adolescent pregnancy was higher among those who initiated their first sexual intercourse between 10 and 16 years (38.0%; p<0.001), those who used contraceptive methods (40.6%; p<0.001), individuals who did not know the time of the cycle when they could become pregnant (35.0%; p<0.001) and those who did not perceive pregnancy as a problem (39.4%; p<0.001) (Table 2).

When we performed the multivariate analysis, we found that the factors independently associated with a higher frequency of teenage pregnancy were as follows: Being in late adolescence (aPR: 1.38; 95%CI: 1.22–1.56), having a partner (aPR: 4.08; 95%CI: 3.46–4.81) and belong to the Quechua ethnicity group (aPR: 1.20; 95%CI: 1.09–1.32). The factors associated with a lower frequency of adolescent pregnancy were as follows: Being in an occupation (aPR: 0.81; 95%CI: 0.75–0.88), currently studying (aPR: 0.42; 95%CI: 0.36–0.49), and belonging to the second (aPR: 0.91; 95%CI: 0.84–0.98), third (aPR: 0.80; 95%CI: 0.72–0.89), fourth (aPR: 0.76; 95%CI: 0.64–0.89) and fifth (aPR: 0.55; 95%CI: 0.41–0.73) wealth quintile. Similarly, to have initiated sexual relations between 17-19 years of age (aPR: 0.52; 95%CI: 0.46–0.59), to perceive a future pregnancy as non-problematic (aPR: 0.77; 95%CI: 0.70–0.83) and to know the moment in the cycle when she could become pregnant (aPR: 0.84; 95%CI: 0.76–0.93) were also associated with a lower prevalence of teenage pregnancy (Table 3).

Factors associated with teenage pregnancy in urban and rural areas are presented in Table 4 and Table 5, respectively.

Discussion

In Peru, about three in 10 adolescents between 15 and 19 years of age who have initiated sexual relations have had at least one pregnancy. The high prevalence of adolescent pregnancy could favor the appearance of a higher rate of obstetric and perinatal complications in this group.⁵ It was found in the present study that older age (17 to 19 years), the presence of a partner, ethnicity, having a job, being in school, level of wealth, early initiation of sexual relations (≤16 years), the perception of a future pregnancy as non-problematic, and knowledge of the moment in the cycle when pregnancy may occur were independently associated with adolescent pregnancy.

We found that belonging to late adolescence (between 17 to 19 years) was associated with a higher prevalence of teenage pregnancy. This is consistent with previous studies^16,17 and could be explained by the greater development and mental maturity in this group to assume a pregnancy, as well as a greater development of female identity and greater capacity to adapt to parenting roles.³ Similarly, the literature has described a greater desire to become pregnant in late adolescence compared to the rest of adolescence.¹⁸ Furthermore, it should be taken into account that the sociocultural and economic context could influence the age of onset of risky sexual behaviors in adolescents,¹⁹ which could lead to a higher risk of becoming pregnant.

The presence of a partner among the adolescents was associated with a higher prevalence of teenage pregnancy. In this regard, this association was previously evidenced in studies focusing on sexually active adolescents.^20,21 In Latin American countries, the high prevalence of adolescent pregnancy could be due to the fact that among adolescents with a partner there is a greater desire to become pregnant and achieve motherhood in order to start a family at an early age.²² In Peru, it has been reported that 69% of adolescents aged 15 to 19 years who were pregnant or had children were in some type of early union (65.8% cohabiting and 3.2% married).²³ Thus, the association with the presence of a partner could be due to the fact that after adolescents become pregnant, parents put pressure on the couple to marry or cohabit. Given that, family planning measures should be widely encouraged for both female and male adolescents.

We also found that belonging to the Quechua ethnicity group was associated with a higher prevalence of adolescent pregnancy. In this regard, it has been reported that women from ethnic minorities tend to experience social and economic exclusion, which could generate greater inequity in access to family planning services and contraceptive methods,^24,25 leading to higher maternal mortality.²⁶ In Peru in 2016, it was observed that the population of native origin (Quechua, Aymara or Amazonian origin) had a higher level of fertility and a lower proportion of contraceptive methods used.²⁷ In these ethnic groups, a greater acceptance of early marriage and pregnancy has also been reported.²⁵ Therefore, greater state intervention is required in these population groups to reduce the gaps in access to sexual and reproductive health information for adolescents.

Having an occupation or being a student was associated with a lower frequency of adolescent pregnancy. Adolescents who engage in these activities may prioritize education or economic income over starting a family.²⁸ This contrasts with previous studies conducted in middle- and low-income countries, where a higher risk of pregnancy has been reported among adolescents who do not have an occupation²⁶ or who do not attend school.²⁹ Having an education could be related to a better knowledge of sexual health and a greater ambition to complete higher education, postponing reproductive desire until greater emotional and economic stability is achieved.³⁰ In Peru, dropout at the secondary education level in 2015 was 7.6% among adolescents.³¹ Given this, it would be important to implement national programs that promote and ensure education and find vulnerable adolescents who have dropped out of school.

It was also found in the present study that belonging to the third, fourth or fifth wealth quintile was associated with a lower frequency of adolescent pregnancy. In Latin America and the Caribbean, an early onset of sexual relations³² and a higher proportion of adolescent pregnancy^33–35 were reported among lower income social groups. This could be explained by lower use of and limited access to contraceptive methods in these groups.³⁵ Similarly, unfavorable economic conditions could lead women to think of motherhood as a better life option, since they would have a partner to take care of household needs.^16,17 In Peru, the “Juntos” Program was implemented in 2005 with the aim of reducing the impact of poverty and its intergenerational transmission through the bimonthly delivery of a monetary incentive of 200 nuevos soles (S/200) to low income households, plus an additional S/100 for pregnant women who attend antenatal visit care and S/100 for each child under 3 years of age who comply with growth and development checkups.³⁶ This initiative could favor vulnerable groups such as pregnant adolescents in low socioeconomic strata.

Regarding the age of initiation of sexual intercourse, we found that late initiation of sexual intercourse (17 to 19 years) was associated with a lower prevalence of adolescent pregnancy. This finding is consistent with the literature,²⁰ which has reported earlier ages of sexual intercourse,^32,37 and higher proportions of a first pregnancy between 15 and 19 years of age.³⁸ This could be explained by the lack of promotion of sexual and reproductive health information, including family planning methods, at earlier ages. Therefore, the general population should be made aware of the importance of regulating access to sexual and reproductive health information from puberty and adolescence.

Another variable that was associated with a higher prevalence of adolescent pregnancy was the perception of a future pregnancy as non-problematic in the crude analysis. In this regard, it has been previously reported that a positive attitude toward pregnancy among postpartum adolescents is strongly associated with a higher prevalence of a second pregnancy.³⁹ Likewise, a greater likelihood of feeling stigmatized during pregnancy has been observed when they did not have a romantic relationship with a partner or felt verbally abused by family, friends, partners or other adolescents.⁴⁰ This could be due to the fact that the greater emotional stability achieved through the support of a partner and family, friends and social environment during pregnancy could generate a non-problematic perception of a subsequent pregnancy.^41,42 However, in our analysis, when adjusting for other variables, we found a reversal in the direction of the association. This could be explained by the fact that the sample evaluated included adolescents with no history of pregnancy, who could have a biased perception of a possible pregnancy and be influenced by the desire to start a family. This explanation is consistent with the fact that there is a high prevalence of desire for pregnancy among adolescents in Latin America.²²

Knowledge of the moment in the cycle when pregnancy is possible was associated with a lower prevalence of adolescent pregnancy. This is consistent with previous studies, where ignorance of the fertile days was a risk factor for adolescent pregnancy.¹⁶ Thus, among adolescents with a greater concern for avoiding unwanted pregnancy, it was reasonable that there is greater interest in knowing the dates of the cycle when there is a greater probability of becoming pregnant.⁴³

Conclusions

Between 2015 to 2019, in Peru about a third of adolescents aged 15 to 19 years who initiated sexual activity, presented with at least one pregnancy. We identified that being between 17 and 19 years old, having a partner and being of Quechua ethnicity were independently associated with a higher prevalence of adolescent pregnancy. On the other hand, having an occupation, being in school, belonging to the second, third, fourth and fifth quintiles of poverty, having had their first sexual intercourse between 17 and 19 years of age, perceiving a future pregnancy as non-problematic and knowing the moment in the cycle when they could become pregnant were independently associated with a lower prevalence of adolescent pregnancy. It is necessary that the sustained increase of local and national strategies regarding family planning and sexual education in adolescents be carried out in a timely and inclusive manner, given that the avoidance of early initiation of sexual relations together with the acquisition of competencies on adolescent pregnancy prior to the initiation of sexual relations is a reasonable option to reduce the prevalence of adolescent pregnancy and therefore potential obstetric-neonatal complications in Peru.

Data availability