According to WHO Adolescents ranged from 10–19 years and they account about 18 % of the global population. They are under physiological, cognitive, and psychosocial changes but remain neglected from many health and nutrition services [1, 2].

The burden of energy, protein and micronutrient deficiencies is high in adolescents of developing courtiers. The subsequent social, economic, health, and development impact of under nutrition in adolescents is expected to be high in this countries [2, 3].

Malnutrition is one of the major public health issue affecting many women in Ethiopia. Twenty seven percent of women had chronic energy deficiency (BMI < 18.5), 17 % of women were anemic, and 6 % of rural women were experiencing night-blindness in their most recent pregnancy [3]. Undernutrition throughout the human life cycle usually starts in uterus and spans generation [4]. Malnutrition that occurs during childhood, adolescence, and pregnancy has an additive negative impact on the birth outcome of the newborn and it will have intergenerational effect. Malnourished adolescents tend to be ultimately malnourished adults and give birth to small babies [3, 5–7]. Moreover Infants with low birth weight are more vulnerable to adult-onset chronic diseases than children born at normal weight [7].

Malnutrition in adolescents may be genetically inherited, however, the vast majority of cases are linked with food insecurity, poor care and poor socioeconomic status [3]. Prematurity, short maternal stature, infections, cigarette smoking, alcohol and drug use, very young maternal age, indoor air pollution, domestic violence, closely spaced pregnancies, hypertension, stress, and malaria are all important predictors for the intergenerational effect of undernutrition [8].

The adolescent growth spurt offers a chance to compensate for earlier growth failure, although such potential is very limited [3]. Adolescence is a pivotal stage of the life cycle, and in turn, provides a unique opportunity to foster a healthy transition from childhood to adulthood and halting generational effect of malnutrition [5].

Large-scale community-based health and nutrition interventions showed promising results in improving nutritional status of adolescents in different countries [9]. In Ethiopia there are community based interventions mainly to prevent malnutrition in women and children, however there is limited effort to address malnutrition in adolescents. The current study aimed to assess the prevalence and associated factors of undernutrition in adolescent girls in Amhara region, Ethiopia. The study will be a base line for other future studies and will guide policy makers to design proper nutrition interventions for adolescents.

This cross sectional nutritional survey was conducted at five CBN implementing woredas of Amhara region. The study determined prevalence and associated factors of undernutrition in adolescent girls. Despite the fact that community based nutrition program will improve the nutritional status of women and children, prevalence of low BMI-for-age and Low height-for-age in adolescent girls were found to be high in the study setting which were 13.6 % and 31.5 % respectively.

The prevalence of low BMI-for-age is comparable with the national nutrition baseline survey report for the NNP of Ethiopia which was14% [15] and lower than a study done in northern part of Ethiopia (58.3 %) [16] and Varanasi rural India (26.6 %) [17]. However, the prevalence is higher than a study in Addis Abeba Ethiopia (6.2 %) [18]. The variation in prevalence could be explained in socioeconomic and urban–rural difference between the study subjects and settings. Low prevalence as compared to the study in northern Ethiopia may be due to the current study was conducted after the introduction of community based program in Ethiopia.

The prevalence of low Height-for-age is higher than the national base line survey which was 23 % [15], northern part of Ethiopia [16] and Addis Abeba town [18]. The reason could be our survey is done in Amhara region in which adolescents may have a different feeding habit. High levels of stunting in the study setting may be due to early marriage and early pregnancy which is high in the region. The other possible reason could be the others were conducted in the age group of 13–19 in which the most vulnerable groups were not included.

In this survey, variation in development of thinness was observed across different age groups. Young adolescent girls were more likely to be thin than older adolescent girls in this study (Table 3). The findings of this study was in line with a study in Northern Ethiopia and Ambo town [16, 19]. This may be due to the fact that age 10–14 is the time of adolescent growth spurt in which there is an increased demand of essential nutrients. Hence, if the requirement for achieving the their maximum need is not fulfilled they will be prone to malnutrition.

The DDS is one of best indicators of both macronutrient and micronutrient intake. The current study revealed that adolescent girls with higher DDS were more likely to have normal BMI-for- age Z scores as compared to those having low DDS (Table 3). This is because when the DDS is high, adolescents will get adequate energy, and other important nutrients having role in growth and development.

Age of adolescent girls was also important predictor of stunting in adolescent girls in which early adolescents aged 10–14 years were more likely to be stunted as compared with those 18–19 years old (Table 4). This finding is consistent with the baseline national nutrition survey and a study in northern Ethiopia [15, 16]. Those early adolescents are at the greatest gain in height as compared to late adolescents. Hence, Failing to achieve their nutrient needs for this period will make early adolescents more susceptible for developing chronic malnutrition.

Adolescents living in food secure households were 35 % times less likely to be stunted than those living in food insecure household (Table 4). This finding is consistent with a study in Jimma Zone, southwest Ethiopia [20]. This is because food security is one of the important determinant of chronic nutritional insult in adolescent girls.

In this study adolescents who had no nutrition and health information were 2 times more likely to be stunted than those who had information (Table 4). This is because adolescents getting nutrition information will change their dietary habit which can improve their nutritional status.

Even though the study is conducted in wider coverage it may not address cause and effect relationship between variables since it is a cross sectional study. There may be recall and social desirability bias in listing food items eaten in the past 24 h. More over DDS did not measure quantity of food eaten by this adolescents.

Prevalence of adolescents with low BMI for age and Height for age Z score less than < −2SD were high. Age, dietary diversity score and CBN service utilization were factors affecting low BMI for Age in adolescent girls. Age, food insecurity and access to Nutrition and health information were factors affecting low height for age in adolescent girls. Considering adolescents as one of major target groups for CBN and give training to health extension workers and Women development army about nutrition services to be delivered to adolescents is recommended.