Adolescence is a vulnerable phase in human development as it represents a transition from childhood to physical, psychological and social maturity. During this period, adolescents learn and develop knowledge and skills to deal with critical aspects of their health and development while their bodies mature. Adolescent girls, especially younger girls, are particularly vulnerable because they face the risks of premature pregnancy and childbirth (UNICEF, http://data.unicef.org/topic/maternal-health/adolescent-health/). The Global Strategy for Women’s, Children’s and Adolescent’s Health 2016-2030 fosters a world in which “every woman, child and adolescent in every setting realises their rights to physical and mental health and well-being, has social and economic opportunities, and is able to participate fully in shaping prosperous and sustainable societies”.
The 1.2 billion adolescents (10-19 years) in the world today represent more than 18% of the global population. In 2015, more than 1.2 million adolescents died. Main causes of adolescent deaths include road injury, lower respiratory infections, self-harm, diarrhoeal diseases, drowning, interpersonal violence and maternal conditions (WHO, UNAIDS, UNFPA, UNICEF, UNWomen, The World Bank Group, 2018). In girls aged from 15-19 years, complications during pregnancy and childbirth are the leading cause of death globally.
Risk factors for NCD, the leading cause of premature adult deaths, are often acquired in adolescence. They include alcohol or tobacco use, lack of physical activity, unprotected sex and/or exposure to violence, which lead to an increased risk of overweight and obesity and diabetes and, ultimately, to a higher risk of NCDs across the life course. As the income level of a country increases, the prevalence of overweight and obesity adolescent increases, and men are more likely to be overweight and obese than women (Figure 4.12). On average across high- and upper-middle income Asia-Pacific countries, more than seven adolescent females and 10 adolescent males were obese in 2016, two and half times the prevalence observed across lower-middle and low income Asia-Pacific countries. A very high increase in the prevalence of obesity among adolescent was reported in Asia-Pacific, in particular in upper-middle and lower-middle and low-income countries (Figure 4.13). In China, India and Viet Nam, the prevalence of obesity doubled from 2010-16 for both males and females adolescents.
Adolescent pregnancies are a global problem that occurs in high, middle, and low income countries. Around the world, adolescent pregnancies are more likely to occur in marginalised communities, commonly driven by poverty and lack of education and employment opportunities. For some adolescents, pregnancy and childbirth are planned and wanted. However, for many adolescents, pregnancy and childbirth are neither planned nor wanted. Adolescents face barriers to accessing contraception including restrictive laws and policies regarding provision of contraceptive based on age or marital status, health worker bias and/or lack of willingness to acknowledge adolescents’ sexual health needs, and adolescents’ own inability to access contraceptives because of knowledge, transportation, and financial constraints. Adolescent pregnancy remains a major contributor to maternal and child morbidity and mortality, increased preterm births and low birthweight and to intergenerational cycles of ill-health and poverty. Adolescent pregnancy can also have negative social and economic effects on girls, their families and communities. Around 3.9 million unsafe abortions among girls aged 15-19 years occur each year, contributing to maternal mortality and lasting health problems (Darroch et al., 2016). Unmarried pregnant adolescents may face stigma or rejection by parents and peers and threats of violence. Similarly, girls who become pregnant before age 18 are more likely to experience violence within marriage or a partnership. With regards to education, school-leaving can be a choice when a girl perceives pregnancy to be a better option in her circumstances than continuing education, or can be a direct cause of pregnancy or early marriage. In lower-middle and low-income Asia-Pacific countries, one out of twenty women aged 15-19 give birth (Figure 4.14), twice the rate observed in upper-middle Asia-Pacific countries. In Lao PDR and Bangladesh, this proportion doubles to one out of ten adolescent giving birth.