Introduction

The impact of teen pregnancy among teenagers in both developed and developing countries has been a major topic of discussion for decades now. Much of research efforts have been focused on the causes and consequences of these pregnancies on social, educational and health dimensions of adolescent mothers. Moreover, some studies suggest that adolescent pregnancies jeopardize educational prospects and economic opportunities for women (Sedgh et al., 2015).

A majority of adolescent pregnancies occur in middle and low-income countries; in the year 1997, close to 16 million births to teenage mothers happened in developing countries (Beliza, Conde-agudelo, and Lammers, 2005). Overall, 15 to 20% of births in developing countries are to adolescent mothers. Furthermore, it is estimated that 85% of teen mothers reside in developing countries and 25% of maternal mortality occurs in this subpopulation (Neal et al., 2016). Despite the drop in adolescent births in developed countries in Africa, Latin America and the Caribbean still struggle with the problem of teen pregnancies (Tunick, 1996). Thus the question of adolescent pregnancy remains to be a formidable global challenge.

Underdeveloped countries continue to bear the most significant percentage of uneducated young girls and women accelerating the incidences of early marriages and early pregnancy. Furthermore, culture plays a core role in driving up the figure of early pregnancies in low and middle-income countries (Kothari et al., 2012). According to the World Health Organization (WHO), an estimated 16 million girls aged between 15 and 19 years and 2.5 million under the age of 16 years girls are impregnated each year in low and middle-income countries (Darroch et al., 2016). Sub-Saharan Africa harbors the largest share of these adolescents’ pregnancies. In high-income countries, the rate of adolescent pregnancies is a bit lower as compared to low-income countries. Approximately, 5 to 10 % of young girls in high-income countries are early pregnancies (Gilbert et al., 2009).

Complications during the gestation period and birth have been implicated as the primary cause of maternal death for 15 to 19 years old girls. It is estimated that in every year about 3.9 million girls between the age of 16 and 19 undergone unsafe abortions increasing the chances of maternal death among adolescent (WHO and Mathers, 2016). Teen mothers between 10 and 19 years are faced with an elevated risk of developing eclampsia, puerperal endometritis and systemic infections which have for many decades been the leading cause of death among teen mothers (Klein, 2005; Baldwin et al., 2019)

In 2011, the WHO published guidelines for preventing early pregnancies from reducing the global impact of these pregnancies. The instructions aimed to achieve six main objectives. Firstly, the guidelines aimed at reducing early pregnancy by 10% and a reduction of maternal deaths by 70%. Building support for the reduction of early pregnancies, increasing the uptake of contraceptives among adolescents, reducing case of rape, reducing unsafe abortions and increasing skilled antenatal care are among the critical objective drive by the WHO guidelines on adolescent pregnancies (Kozuki et al., 2013). In both low and high-income countries, adolescent pregnancies have been associated with high incidence of various adverse maternal and perinatal outcomes including low birth weight (LBW), stillbirths, preterm births, as well as small-for-gestational-age (SGA) (Read et al., 2016). This paper explores various aspects of adolescent pregnancy concerning the adverse effects of teen pregnancy. The article also provides possible intervention measures which can be implemented to mitigate the problem of adolescence pregnancy.

Factors contributing to adolescent pregnancy

Various factors ranging from the level education to poverty have been suggested to exacerbate the problem of teenage pregnancy particularly in low-income countries (Black and DeBlassie, 1985). Drugs and alcohol intake is a significant contributor to the high rates of adolescence pregnancies in low-income countries. Accumulating evidence suggests that substance use among adolescents is a predisposing factor to unplanned pregnancies. Alcohol exposes adolescents to toxic peer influence which more often than not result in unsafe sex and pregnancies. According to Connery and colleagues, alcohol intake has been ranked as the leading cause of teenage pregnancies in the USA (Connery, Albright, and Rodolico, 2014). The rate of alcohol intake in low-income countries particularly in remote, underdeveloped countries is alarming. In 2003 European countries including Denmark, Sweden, Slovenia, Finland, and the Netherlands recorded the lowest teen birth rates (6/1,000) while the United Kingdom (27/1,000) reported the highest standards in Europe (Reime, Schücking and Wenzlaff, 2008).

Alcohol intake behavior among adolescents is an increasing trend that predisposes the teenagers to unsafe sex and early pregnancies (WHO, 2014).  Moreover, alcohol and drug intake are associated with poverty and lack of education. In African rural regions where poverty has taken its toll on families, cases of adolescent pregnancies are said to be high. Families living in pervasive poverty are not able to afford education for their young girls (Neal, Channon and Chintsanya, 2018). Educating girls plays a crucial role in ensuring that they attain their goals in life, thus reducing the chances of early pregnancy. Poverty may also drive you adolescent girls into early marriages and unplanned sex in exchange for money (Young et al., 2004).

Low- level education is another key driver to the increasing global rates of adolescent pregnancy. Adolescent age between 15 and 19 years is within the school going bracket and studies have shown that in areas where education is emphasized adolescent pregnancies are lower as compared to areas where education is not valued. For instance, a study by Brindis among the Hispanic school-going age adolescents showed that education played an essential role in delaying pregnancy among Hispanic youths. The author demonstrated that the rates of adolescent pregnancies were higher among Hispanic teenagers living in the underdeveloped area with poor access to education facilities (Brindis, 1992). Poor education is closely linked to poor socio-economic status and poverty (Markovitz et al., 2005). Majority of adolescents living in poverty-stricken areas particularly in sub-Saharan Africa are more vulnerable to adolescent pregnancies as compared to those who live in communities with well-established systems for education (Paranjothy et al., 2009).

Media has a profound effect on adolescents in terms of sexuality. Media provides a platform for information dissemination and knowledge gain which can empower youths and sensitize them on the hazards of adolescent sex and pregnancy. However, the birth of a domain of media known as social media has brought about a myriad of effects on youths particular on the content of information shared on this media platform. Through social media, adolescents have access to uncensored content that may encourage sex in this population. Information such as pornographic content is inappropriate for youths aged between 15 and 19 years (Strasburger, 1989). Uncontrolled use of media encourages adolescent sexuality and pregnancies. In the same breadth, peer influence is another predisposing factor to Adolescent sexuality and fertility. Some youths fall in the trap of early pregnancy due to the urge to imitate their peers and falling prey of the ill-advice provided by their peers (Klein, 2005).

Maternal age and adverse birth outcomes

Maternal age is a key determinant of birth outcomes (Muganyizi and Kidanto, 2009). The causes of adverse birth outcomes are multifaceted and are not clearly understood, however, there are various indicators for adverse birth outcomes including: such as stillbirth, preterm birth, low birth weight, small for gestational age (SGA), macrosomia, neonatal death, and congenital anomaly. Furthermore, birthweight and gestational age are predictors of neonatal morbidity and mortality (Muganyizi and Kidanto, 2009). Studies have demonstrated that teenage pregnancies suffer a higher risk for stillbirth, preterm birth as well as low birth weight (Mousiolis et al., 2013).

There are similarities in the adverse birth outcomes between adolescent mothers and older mothers. Some of the common adverse birth outcomes in both groups include stillbirth, abortion, gestational diabetes, hypertension among others (Read et al., 2016). In a study aimed to assess the risk associated with mother’s age during pregnancy, a total of 2, 123, 175 births were evaluated. The findings of the study suggested that the risk of adverse effects were higher in the extreme maternal ages (Mousiolis et al., 2013). Notably, the study showed that adverse effects such as stillbirth, neonatal death, congenital disorders, lower birth weight, and preterm birth were common among the adolescent older age pregnancies. Thus, the adverse birth outcomes inherent to teenage pregnancies are also observed among older age pregnancies underpinning the similarities between the adolescent and old age pregnancy (Mousiolis et al., 2013). On the other hand, gestational diabetes is a common pregnancy complication that has been observed in pregnant women despite the age of the pregnancy (Langille, 2007).

Increasing evidence suggests that adolescent and old age pregnancies are also associated with other health complications such as hemorrhagic syndromes, urinary infections, high blood pressure, premature rapture hemorrhage and pre-eclampsia and eclampsia (Azevedo, Diniz and Evangelista, 2015). Studies have also shown that sexuality in adolescent age increases the risk and frequency of sexually transmitted diseases. Other studies investigating the biological impact of adolescent and older age pregnancies suggests that these pregnancies are associated with high rates of high blood pressure, gestational diabetes, birth complications and neonatal mortality (Azevedo, Diniz and Evangelista, 2015). Low birth weight is also a common problem associated with adolescent and older age pregnancies. Studies have also shown that poor health outcome is related to the quality of care provided to pregnant women during the pregnancy period.

Teenage mothers have limited access to quality care due to lack of resources and in part due to the negligence of prenatal care as a result of stigma and denial (Lopoo, 2011). Moreover, it has been proven biologically that it is possible for the teenagers who are still growing and may end up competing for nutrients with the developing fetus. The eventual outcome of such a competition is that the fetus will be deprived of essential nutrients required for fetus development (Johnson and Moore, 2016). Despite the limited research in the area of labor and complications during delivery, some studies have delved into the complexities likely to affect teenage mothers during pregnancy known as potentially avoidable maternal complications. These complications include urinary infections, ectopic pregnancies, pre-mature membrane rapture, and inadequate prenatal care. These complications remain to be significant concerns in adolescent pregnancy despite being easy and simple to prevent (Lopoo, 2011).

Adolescent pregnancy and maternal health

Adult pregnancy is confronted with a significant psychiatric health challenge and impacts negatively on maternal health as well as the developing fetus. A secondary outcome of such psychopathy during pregnancy is the impairment of mother-child bonding. Depression during pregnancy is also an accelerator of adverse birth outcomes such as preterm births, behavioral differences and low birth weight (Khashan, Baker and Kenny, 2010). Depression during the period of pregnancy can potentially result in postpartum depression and can be associated with maternal suicide and infanticide (Siegel and Brandon, 2014).

The normal fetal development depends on the supply of nutrients from the mother, particularly amino acids. Therefore, adequate placental transport of amino acid is an essential prerequisite for fetal growth. Studies have shown that the placental transport of amino acid in adolescents is not efficient enough to serve the purpose of fetus development (Hayward et al., 2019). The reduced transport across the placenta is the primary cause of low birth weight among adolescent mothers (Hayward et al., 2019). In mature women, placental transport tends to be more efficient, thus serving the nutritional needs of the growing fetus and evading the problem of low birth weight. The health consequences of reduced placental transport in adolescent pregnancy is manifested in terms of preterm births, respiratory diseases, complications during delivery, and child mortality (Hayward et al., 2019). The manifestation of poor placental transport reflects poor nutrition of the fetus resulting in health issues such as the ones mentioned above.

Prevention and control

A critical public health approach in the prevention of teenage pregnancies and their adverse outcome is the prevention of second pregnancy. Health care providers are the key stakeholders in the fight against adolescent pregnancy and must be involved fully in the fight. The WHO provides detailed guidelines for prevention/reeducation of teenage pregnancy. For instance, the WHO recommends the prevention of early marriages particularly in communities where culture forces young girls to drop out of school and get married to older men (Weng, Yang, and Chiu, 2014). Such trends have been observed in some African cultures (Chandra-mouli et al., 2013). Other recommendations include enhancing sexuality education to help reduce the incidences of teenage sex and early marriages. Increasing opportunities for girl-child education has also been recommended under the WHO guidelines. Creating systems for economic and social support programs particularly in rural and remote areas is a promising approach towards a reduction of the adolescent pregnancies (Ganchimeg et al., 2014). Increased use of contraceptives, reducing forced sex, preventing unsafe abortion and enhancing prenatal care are some of the recommendations that when affected can help to control the problem of adolescent pregnancy.

Nutritional intervention is another important approach to mitigate adverse outcomes associated with childbirth in adolescent mothers. Some of the critical interventions include the supplementation of folic acid during pregnancy. Folic acid is very useful in the prevention of defects in the development of neural tubes. A research study showed a 72% reduction in the risk of neural tube development problems (Bhutta et al., 2013). Supplementation of iron has also demonstrated a positive outcome during pregnancy. For instance, supplementation of metal with another vitamin significantly reduced the risk of anemia by 27% (Bhutta et al., 2013). Other nutrients that can be supplemented during pregnancy to produce positive outcome include micronutrients, calcium, and iodine. Apart from mineral and vitamin supplementation, addressing the problem of a well-balanced diet is key to prevention of birth associated with adverse outcomes. Carbohydrate and protein should be supplied in adequate amounts to cater to the mother’s needs as well as those of the developing fetus. For the neonates, interventions include the delay in clamping the cord, administration of vitamin K, kangaroo mother care especially for the preterm babies and those born with LBW. The infants need to be boosted by the mother’s milk through breastfeeding and dietary diversity to ensure the inclusion of all nutrients and minerals (Bhutta et al., 2013).