Abstract

This ecological study aimed to analyze the trend of the nutritional status of pregnant adolescent beneficiaries of the Brazilian Bolsa Família conditional cash transfer program in the 2008-2018 period. We evaluated secondary data of pregnant adolescent beneficiaries of the Bolsa Família Program from January 2008 to December 2018, extracted from the public reports of the WEB Food and Nutrition Surveillance System. We accessed the monitoring reports on the consolidated public-access health conditionalities of the Bolsa Família Program, always considering the second validity. An annual variation of -1.2% (95%CI: [-1.6; -0.8] p<0.01) was observed in the prevalence of underweight in Brazil in the studied sample. The prevalence of overweight and obesity in the country had annual variations of 2.9% (95%CI: [2.0; 3.7] p<0.01) and 7.5% (95%CI: [5.7; 9.3] p<0.01), respectively. We conclude by saying, that, in the evaluated period, the prevalence of underweight among pregnant adolescent beneficiaries of the Bolsa Família Program showed a decreasing trend, while the prevalence of overweight and obesity increased throughout Brazil.

Key words:
Pregnancy in adolescence; Nutrition assessment; Nutritional surveillance; Health information systems

Introduction

Adolescent pregnancy is a global public health issue due to its biological, psychological, economic, family, and educational consequences, which can reverberate over a country’s social, economic, and health indicators¹1 United Nations Population Fund (UNFPA). Motherhood in childhood: facing the challenge of adolescent pregnancy. New York: UNFPA; 2013.. According to the World Health Organization (WHO), adolescence is the transition period between childhood and adulthood, starting at 10 and extending to 19 years of age²2 World Health Organization (WHO). Young people's health: a challenge for society. Geneva: WHO; 1986.. The WHO estimates indicate that 16 million adolescents aged 15-19 years become pregnant each year, equivalent to about 11% of total global births³3 World Health Organization (WHO). WHO Guidelines on Preventing Early Pregnancy and Poor Reproductive Outcome Among Adolescents in Developing Countries. Geneva: WHO; 2011.. In Brazil, the estimated prevalence of pregnant women in this same age group is 11.8%⁴4 Rodríguez Vignoli J. La reproducción en la adolescencia y sus desigualdades en América Latina: introducción al análisis demográfico, con énfasis en el uso de microdatos censales de la ronda de 2010. Santiago: Comisión Económica para América Latina y el Caribe; 2014.. According to data from the report published by the United Nations (UN), the adolescent pregnancy rate in Brazil is 68.4 births for every 1,000 adolescents, exceeding Latin American/Caribbean and global rates (65.5 and 46.0 births for every 1,000 adolescents, respectively)⁵5 Pan American Health Organization (PAHO). United Nations Population Fund and United Nations Children's Fund (UNICEF). Accelerating progress toward the reduction of adolescent pregnancy in Latin America and the Caribbean. Report of a technical consultation. Washington D.C.: PAHO, UNICEF; 2016..

Pregnancy in this stage of the life cycle further increases the already high energy and nutritional needs, given that this phase is characterized by the completion of the height growth process, body weight and bone mass increase, maturation of sexual organs, body composition changes, which can cause competition for nutrients between the mother and the fetus and promote a decreased linear growth of mothers⁶6 Gigante DP, Rasmussen KM, Victora CG. Pregnancy increases BMI in adolescents of a population-based birth cohort. J Nutr 2005; 135(1):74-80.^,77 Rah JH, Christian P, Shamim AA, Arju UT, Labrique AB, Rashid M. Pregnancy and Lactation Hinder Growth and Nutritional Status of Adolescent Girls in Rural Bangladesh. J Nutr 2008; 138(8):1505-1511.. Moreover, the risks of adverse outcomes for the mother-child binomial in this age group have been reported in the scientific literature, and the main ones were low birth weight, prematurity, stillbirth, pre-eclampsia, feeling of social isolation, maternal depression, and delay or neglected maternal education⁸8 Azevedo WF, Diniz MB, Fonseca ESV, Azevedo LMR, Evangelista CB. Complicações da gravidez na adolescência: revisão sistemática da literatura. Einstein 2015; 13(4):618-626.

9 Ganchimeg T, Ota E, Morisaki N, Laopaiboon M, Lumbiganon P, Zhang J, Yamdamsuren B, Temmerman M, Say L, Tunçalp O, Vogel JP, Souza JP, Mori R, WHO Multicountry Survey on Maternal Newborn Health Research Network. Pregnancy and childbirth outcomes among adolescent mothers: a world health organization multi country study. BJOG 2014; 121(Supl. 1):40-48.^-1010 Nguyen PH, Sanghvi T, Tran LM, Afsana K, Mahmud Z, Aktar B, Haque R, Menon P. The nutrition and health risks faced by pregnant adolescents: insights from a cross -sectional study in Bangladesh. PLoS One 2017, 12(6):e0178878..

Adolescent pregnancies seem to be significantly influenced by social and economic issues. The WHO estimated that about 95% of births to mothers aged 15-19 years occur in developing countries³3 World Health Organization (WHO). WHO Guidelines on Preventing Early Pregnancy and Poor Reproductive Outcome Among Adolescents in Developing Countries. Geneva: WHO; 2011.. This condition is driven by poverty, low schooling, social, sexual, and gender exclusion, lack of job opportunities, and early relationship/marriage⁵5 Pan American Health Organization (PAHO). United Nations Population Fund and United Nations Children's Fund (UNICEF). Accelerating progress toward the reduction of adolescent pregnancy in Latin America and the Caribbean. Report of a technical consultation. Washington D.C.: PAHO, UNICEF; 2016.^,1111 Santelli JS, Song X, Garbers S, Sharma V, Viner RM. Global trends in adolescent fertility, 1990-2012, in relation to national wealth, income inequalities, and educational expenditures. J Adolesc Health 2017; 60(2):161-168.. In this context, adolescent pregnancy contributes to the maintenance of intergenerational cycles of poverty, exclusion, and marginalization, characterized by a higher risk of poverty and worse health-related outcomes in the children of adolescent mothers⁵5 Pan American Health Organization (PAHO). United Nations Population Fund and United Nations Children's Fund (UNICEF). Accelerating progress toward the reduction of adolescent pregnancy in Latin America and the Caribbean. Report of a technical consultation. Washington D.C.: PAHO, UNICEF; 2016..

Conditional cash transfer programs such as the Bolsa Família Program (BFP) in Brazil are recognized worldwide for relieving the poverty of their beneficiaries, increasing the use of health services, and improving the health indicators of children and adults¹²12 Gertler P. Final report: the impact of PROGRESA on health. Washington, DC: Food Policy Research Institute; 2000.

13 Soares FV. Brazil's Bolsa Família: a review. Econ Polit Weekly 2011; 46:55-60.^-1414 Shei A, Costa F, Reis MG, Ko AI. The impact of Brazil's Bolsa Família conditional cash transfer program on children's health care utilization and health outcomes. BMC Int Health Hum Rights 2014; 14:1-10.. The BFP can be considered one of the most important initiatives of the Brazilian government in the fight against poverty in the country and resulted from the unification of the existing cash transfer programs. It was implemented by the Federal Government in 2003, through Provisional Measure Nº 132, which was later enacted as Law N° 10.836, of January 9, 2004. The program grew and became the largest globally, paying out more than R$ 31 billion to 14 million beneficiaries in 2019 alone¹⁵15 Controladoria Geral da União. Portal da Transparência [Internet]. [acessado 2020 fev 10]. Disponível em: http://www.portaltransparencia.gov.br.
http://www.portaltransparencia.gov.br... .

The BFP consists of a direct conditional cash transfer program for the immediate relief of poverty to improve the development of human capital through greater access to education, health, and the promotion of food security in the long term. Some of the conditions of the BFP program in health for pregnant women is the duty to attend prenatal care visits with the monitoring of nutritional status, vaccination according to the calendar recommended by the Ministry of Health, and participate in educational activities on breastfeeding, guidelines for healthy eating for pregnant women and preparation for childbirth. In order to increase protection for the mother and child and increase household income, the BFP establishes that households benefiting from the BFP with pregnant women identified in health care establishments should receive nine monthly installments of the Pregnant Women Variable Benefit. With this action, the program seeks to provide monetary aid and become an instrument to promote equity in access to basic social rights¹⁴14 Shei A, Costa F, Reis MG, Ko AI. The impact of Brazil's Bolsa Família conditional cash transfer program on children's health care utilization and health outcomes. BMC Int Health Hum Rights 2014; 14:1-10.^,1616 Brasil. Ministério da Saúde (MS). Secretaria de Atenção à Saúde. Departamento de Atenção Básica. Marco de referência da vigilância alimentar e nutricional na atenção básica. Brasília: MS; 2015.^,1717 Brasil. Ministério do Desenvolvimento Social. Secretaria de Avaliação e Gestão da informação. Manual do pesquisador. Brasília: Ministério do Desenvolvimento Social, Programa Bolsa Família; 2018..

However, a review study that assessed the impacts of BFP on promoting food security among beneficiaries (not selecting a specific age group), through the assessment of financial expenditure on food, food consumption, hemoglobin levels, food insecurity, and anthropometric data, observed the following paradox: while the program promotes an increasing access to food in terms of quantity, this increase is not necessarily accompanied by higher nutritional quality of purchased foods¹⁸18 Cotta RMM, Machado JC. Programa Bolsa Família e segurança alimentar e nutricional no Brasil: revisão crítica da literature. Rev Panam Salud Publica 2013; 33(1):54-60.. Lignani et al.¹⁹19 Lignani JB, Sichieri R, Burlandy L, Salles-Costa R. Changes in food consumption among the Programa Bolsa Família participant families in Brazil. Public Health Nutr 2010; 14:785-792. also observed that a higher purchasing power of families benefiting from the program increased the consumption of high-energy density processed foods, possibly associated with the lower cost of these foods, which contributes to a higher prevalence of nutritional deviations in the program’s beneficiaries. Thus, this work aimed to analyze the trend of the nutritional status of pregnant adolescents who are beneficiaries of the BFP in the 2008-2018 period.

Methods

This ecological study evaluated the secondary data of pregnant adolescent beneficiaries of the BFP from January 2008 to December 2018 were evaluated, extracted from the public reports of the Sistema de Vigilância Alimentar e Nutricional (SISVAN) Web (http://sisaps.saude.gov.br/sisvan/relatoriopublico/index, accessed 15/12/2019). Filters “pregnant women” and “adolescents”, and the “Bolsa Família management system (DATASUS)” for the data source system were used to generate the report. The Brazilian consolidated data were shown and stratified according to the Federation Units (FU) and the North, Northeast, Midwest, Southeast, and South macro-regions of the country.

The nutritional status of pregnant women available on SISVAN Web is classified per the Body Mass Index (BMI) graph according to the gestational week proposed by Atalah et al.²⁰20 Atalah SE, Castillo LC, Castro SR, Aldea A. Propuesta de un nuevo estándar de evaluación nutricional en embarazadas. Rev Med Chil 1997; 125(12):1429-1436.. This instrument proposes four categories of nutritional status: underweight, normal weight, overweight, and obesity. It is noteworthy that this classification of nutritional status is not specific for pregnant adolescents, but according to the Ministério da Saúde do Brasil guidelines for collection in health services, can be used in this audience provided that the interpretation of the results is flexible and specificity of the group in question is considered²¹21 Brasil. Ministério da Saúde (MS). Secretaria de Atenção à Saúde. Departamento de Atenção Básica. Orientações para coleta e análise de dados antropométricos em serviços de saúde: norma técnica do Sistema de Vigilância Alimentar e Nutricional - SISVAN. Brasília: MS; 2011..

The monitoring reports on the consolidated health conditions of public access of the BFP were accessed to determine the percentage of nutritional follow-up coverage for pregnant women benefiting from the BFP, always considering the second term (https://bfa.saude.gov.br/relatorio/consolidated and http://bolsafamilia.datasus.gov.br/w3c/bfa_relconsol.asp, accessed 16/12/2019). This coverage considers the number of pregnant women benefiting from the program located by health teams and the number of pregnant women whose nutritional data were included in the information systems.

This study was not submitted to the Research Ethics Committees and the National Research Ethics Commission for evaluating the system, considering that it is a research using public domain databases, as provided resolution N° 510 of April 7, 2019 of the National Health Council.

After extraction, data were tabulated and double-entered independently in spreadsheets and then validated. The relative variation in the prevalence of nutritional deviations in the period was calculated with the following formula: relative variation=((P2-P1)/P1)*100, where P2 corresponded to the prevalence of nutritional deviation in 2018 and P1 to the prevalence in 2008. Prevalence and the confidence intervals (CI) for population proportions were presented for each year of the evaluated period (2008-2018).

Then, the generalized linear analysis by Prais-Winsten²²22 Antunes JLF, Cardoso MRA. Uso da análise de séries temporais em estudos epidemiológicos. Epidemiol Serv Saude 2015; 24(3):565-576. was used to assess the trend of time series. In the model, the prevalence of nutritional status (underweight, overweight, and obesity) was the dependent variable, and the evaluative years was the independent variable. The Durbin-Watson test was applied to verify the autocorrelation of the series. The method suggested by Antunes and Cardoso²²22 Antunes JLF, Cardoso MRA. Uso da análise de séries temporais em estudos epidemiológicos. Epidemiol Serv Saude 2015; 24(3):565-576. was used. First, the values of the prevalence of nutritional status were logarithmized. Then, the Prais-Winsten autoregressive model was applied, estimating the beta, minimum beta, and maximum beta values. The annual variation rates and their respective 95%CI were calculated with these values, which can be interpreted as increasing (positive variation rate), stationary (no statistical difference), and decreasing (negative variation rate). Alpha values of 5% were adopted for the statistical significance levels. All statistical analyses were conducted in the R (R Foundation for Statistical Computing, Vienna, Austria) statistical package.

Results

The number of annual observations of pregnant adolescents increased 682.2% from 11,835 to 92,577, from 2008 to 2018. The nutritional status of pregnant adolescents in Brazil had prevalence levels of 37.8% for underweight, 46.9% for normal weight, 12.1% for overweight, and 3.3% for obesity in 2008. In 2018, the prevalence levels of 33.1% of underweight, 43.7% normal weight, 16.4% overweight, and 6.8% of obesity were observed in the country, with positive variations in overweight and obesity compared to 2008 (35.5% and 106.1%, respectively). In contrast, the observed underweight showed a negative relative variation of 12.4%. The other prevalence levels of underweight, normal weight, overweight, and obesity, and relative variations in Brazil and FU in the 2008-2018 period are shown in Table 1. The crude prevalence of nutritional deviations (underweight, overweight, and obesity) in 2008 and 2018 are shown graphically in Figure 1.

Table 2 shows the list of pregnant women located by health teams and region and pregnant women with nutritional data included in the information systems, which shows that in 2008, the Southeast and North regions had the lowest (46.9%) and the highest (66.8%) follow-up percentage, respectively. In 2018, Brazil showed a follow-up of the nutritional data of 87.3% located pregnant adolescents, which is greater than 80% in all five regions of the country.

Table 3 shows the trend analyses of the prevalence of underweight, overweight, and obesity in pregnant adolescents who are BFP beneficiaries in Brazil and its macro-regions. A decreasing trend was observed in the prevalence of underweight in Brazil with an annual variation of -1.2% (95%CI: [-1.6; -0.8] p<0.01), and the South region had the highest annual variation (-1.5%; 95%CI: [-2.1; -0.9] p<0.01). An increasing trend was observed in the country regarding the prevalence of overweight (2.9%; 95%CI: [2.0; 3.7] p<0.01), it is noteworthy that the North region showed the highest annual variation between regions (4.1%; 95%CI: [3.1; 5.2] p<0.01). The prevalence of obesity also showed an increasing trend in the country (7.5%; 95%CI: [5.7; 9.3] p<0.01), and the Midwest (10.2%; 95%CI: [5.3; 15.3] p<0.01) and Northeast (10.1%; 95%CI: [7.8; 12.5] p<0.01) were the regions with the highest annual variations.

Discussion

The study found a decreasing trend in the prevalence of underweight among pregnant adolescents benefiting from BFP in the period evaluated, while the prevalence of overweight and obesity showed increasing trends in all macro-regions of the country. Regarding the coverage of the BFP, we observed an increase in the percentage of pregnant women with nutritional data entered in the information systems during the period evaluated. Although this study did not intend to compare the data of pregnant women in the systems with the coverage of the Family Health Strategy (FHS), it is admissible to believe that this fact is associated with higher FHS coverage throughout the national territory²³23 Pinto LF, Giovanella L. Do Programa à Estratégia da Saúde da Família; expansão do acesso e redução das internações por condições sensíveis à atenção básica (ICSAB). Cien Saude Colet 2018; 23(6):1903-1914..

The findings that point to the growing trend in the prevalence of pregnant overweight adolescents in Brazil and its regions follow the same global pattern in children, adolescents, and adults²⁴24 Seidell JC, Halberstadt J. The Global Burden of Obesity and the Challenges of Prevention. Ann Nutr Metab 2015; 66(Supl. 2):7-12.. Our results indicate that the conditionalities and income transfer currently carried out by the BFP were insufficient to ensure access to food and nutritional security and to reduce the nutritional problems of pregnant adolescent beneficiaries, requiring intersectoral measures geared to households and the community. This simultaneous increase in obesity in the life cycles and perpetuated high prevalence of underweight seems to be driven by changes in global food systems, observed in low- and middle-income countries, resulting from the food transition process that provides more processed, accessible, and energetically dense foods²⁴24 Seidell JC, Halberstadt J. The Global Burden of Obesity and the Challenges of Prevention. Ann Nutr Metab 2015; 66(Supl. 2):7-12.^,2525 Popkin BM, Corvalan C, Grummer-Strawn LM. Dynamics of the double burden of malnutrition and the changing nutrition reality. Lancet 2020; 395:65-74.. Studies describe that this situation leads to an increased risk for chronic non-communicable diseases, showing an intergenerational cycle of disadvantages, a condition that culminates in a high morbidity burden, such as the increase in cardiovascular diseases, type 2 diabetes mellitus, cancer, osteoarthritis, and work disability²⁴24 Seidell JC, Halberstadt J. The Global Burden of Obesity and the Challenges of Prevention. Ann Nutr Metab 2015; 66(Supl. 2):7-12.^,2626 Gray CL, Messer LC, Rappazo KM, Jyotsna SJ, Grabich SC, Lobdell DT. The association between physical inactivity and obesity is modified by five domains of environmental quality in U.S. adults: A cross-sectional study. PLoS One 2018; 13(8):e0203301.^,2727 Wells JC, Sawaya AL, Wibaek R, Mwangome M, Poullas MS, Yajnik CS, Demaio. The Double Burden of Malnutrition: Aetiological Pathways and Consequences for Health. Lancet 2019; 395(10217):75-88.. In women, exposure to this double burden of malnutrition throughout life can lead to major complications in childbirth²⁷27 Wells JC, Sawaya AL, Wibaek R, Mwangome M, Poullas MS, Yajnik CS, Demaio. The Double Burden of Malnutrition: Aetiological Pathways and Consequences for Health. Lancet 2019; 395(10217):75-88.. Furthermore, obesity during pregnancy can increase the risk for several maternal and child complications, such as spontaneous abortion, gestational diabetes mellitus, pre-eclampsia, postpartum thromboembolism, breastfeeding problems, premature birth, stillbirth, macrosomia, and congenital abnormalities²⁸28 Catalano PM, Shankar K. Obesity and pregnancy: mechanisms of short term and long term adverse consequences for mother and child. BMJ 2017; 356:j1..

Fulfilling BFP conditionalities means, for the beneficiary, assuring the exercise of their social rights, especially those of health, education, and social assistance; accessing these services is a basic right and a fundamental condition for breaking with the intergenerational poverty cycle¹⁷17 Brasil. Ministério do Desenvolvimento Social. Secretaria de Avaliação e Gestão da informação. Manual do pesquisador. Brasília: Ministério do Desenvolvimento Social, Programa Bolsa Família; 2018.. The prenatal monitoring data of pregnant women who are beneficiaries of the BFP are entered in SISVAN, a health information system that generates information on the population’s food and nutritional situation, contributing to the knowledge of the nature and magnitude of nutritional problems, identifying geographic areas, social segments, and population groups most at risk of nutritional problems. It is crucial to collect data adequately and feed the system to support the formulation of public policies aimed at improving the patterns of food consumption and the nutritional status of the population¹⁶16 Brasil. Ministério da Saúde (MS). Secretaria de Atenção à Saúde. Departamento de Atenção Básica. Marco de referência da vigilância alimentar e nutricional na atenção básica. Brasília: MS; 2015..

Quality prenatal care is essential for maternal and newborn health. From this perspective, nutritional care consists of nutritional guidelines and continuous monitoring of nutritional status and contributes to the ideal weight gain during pregnancy, avoiding nutritional deviations at this stage²⁹29 Brasil. Ministério da Saúde (MS). Secretaria de Atenção à Saúde. Departamento de Atenção Básica. Manual Instrutivo das Ações de Alimentação e Nutrição na Rede Cegonha. Brasília: MS; 2013.^,3030 Niquini RP, Bittencourt SA, Lacerda, EMA, Saunders C, Leal, MC. Evaluation of the prenatal nutritional care process in seven family health unit in the city of Rio de Janeiro. Cien Saude Colet 2012; 17(10):2805-2816.. A study carried out with adolescent and adult pregnant women who were undergoing prenatal care at a primary health care unit in Rio Grande do Sul sought to investigate the impact of a dietary guidance program on the control of gestational weight gain. It was observed that this procedure was effective in reducing weight gain and clinical complications such as gestational diabetes, pre-eclampsia, underweight, and prematurity³¹31 Vitolo MR, Bueno MSF, Gama CM. Impacto de um programa de orientação dietética sobre a velocidade de ganho de peso de gestantes atendidas em unidades de saúde. Rev Bras Ginecol Obstet 2011; 33(1):13-19..

Adolescent pregnant women alone make up a vulnerable group for nutritional deviations and this is due to several reasons, such as the increased demand for nutrients to subsidize the growth and development of mothers and children in the intrauterine environment and inadequate eating habits. From this perspective, the presence of nutritional deviations in this population is not uncommon. Similar to our findings, a Colombian study carried out with 294 pregnant adolescents, in which 80% of them were in the lowest socioeconomic strata, found 33.7% of underweight and 14.3% of overweight pregnant women³²32 Restrepo-Mesa SL, Zapata NL, Parra BES, Escudero LEV, Betancur LA. Estado nutricional materno y neonatal en un grupo de adolescentes de la ciudad de Medellín. Nutr Hosp 2015; 32(3):1300-1307.. In contrast, data from a survey conducted in Rio de Janeiro showed that about 13% of adolescent mothers accompanied at the maternity ward of a public hospital started their pregnancy with some nutritional deviation, where 1.0% were underweight and 12.0% overweight³³33 Santos MMADS, Baião MR, Barros DCD, Pinto ADA, Pedrosa PLM, Saunders C. Estado nutricional pré-gestacional, ganho de peso materno, condições da assistência pré-natal e desfechos perinatais adversos entre puérperas adolescentes. Rev Bras Epidemiol 2012; 15(1):143-154..

Teenage pregnancy seems to bring unfavorable outcomes, where preterm birth is one of them and is more frequent in adolescents under 15 years of age, according to Karatasli et al.³⁴34 Karatasli V, Kanmaz AG, Inan AH, Budak A, Beyan E. Maternal and neonatal outcomes of adolescent pregnancy. J Gynecol Obstet Hum Reprod 2019; 48(5):347-350., who, as in another study carried out in Turkey, found a high rate of hospitalization in the neonatal intensive care unit for the offspring of these adolescents³⁵35 Kirbas A, Gulerman HC, Daglar K. Pregnancy in Adolescence: Is it an obstetrical risk? J Pediatr Adolesc Gynecol 2016; 29(4):367-371.. Also, teenage pregnancy seems to have negative repercussions for the adolescent’s growth, as shown by Rah et al.⁷7 Rah JH, Christian P, Shamim AA, Arju UT, Labrique AB, Rashid M. Pregnancy and Lactation Hinder Growth and Nutritional Status of Adolescent Girls in Rural Bangladesh. J Nutr 2008; 138(8):1505-1511., where pregnant adolescents had a height difference of 0.35±0.85 cm/year compared to adolescents who never became pregnant. This height deficit associated with underdeveloped pelvic bones and, therefore, a contracted pelvis, may explain the increased risk of pregnant adolescents requiring cesarean delivery³⁴34 Karatasli V, Kanmaz AG, Inan AH, Budak A, Beyan E. Maternal and neonatal outcomes of adolescent pregnancy. J Gynecol Obstet Hum Reprod 2019; 48(5):347-350.^,3636 Shirima CP, Kinabo JL. Nutritional status and birth outcomes of adolescent pregnant girls in Morogoro, Coast, and Dar es Salaam regions, Tanzania. Nutrition 2005; 21(1):32-38..

Methods for anthropometric assessment of pregnant women are fragile, especially when considering that the instruments developed by the Institute of Medicine³⁷37 Institute of Medicine. Full-sized BMI and weight gain charts. Supplementary materials for nutrition during pregnancy and lactation: an implementation guide. Washington, DC: National Academy Press; 1992.^,3838 Institute of Medicine, National Research Council. Committee to Reexamine IOM Pregnancy Weight Guidelines; Rasmussen KM, Yaktine AL, editores. Weight gain during pregnancy: reexamining the guidelines. Washington, DC: National Academies Press; 2009. and the Atalah et al.²⁰20 Atalah SE, Castillo LC, Castro SR, Aldea A. Propuesta de un nuevo estándar de evaluación nutricional en embarazadas. Rev Med Chil 1997; 125(12):1429-1436. nomogram have been scarcely validated in Latin American countries, which suggests caution in the process of comparability to epidemiological contexts with different socio-environmental phenotypes and conditions²⁰20 Atalah SE, Castillo LC, Castro SR, Aldea A. Propuesta de un nuevo estándar de evaluación nutricional en embarazadas. Rev Med Chil 1997; 125(12):1429-1436.^,3737 Institute of Medicine. Full-sized BMI and weight gain charts. Supplementary materials for nutrition during pregnancy and lactation: an implementation guide. Washington, DC: National Academy Press; 1992.

38 Institute of Medicine, National Research Council. Committee to Reexamine IOM Pregnancy Weight Guidelines; Rasmussen KM, Yaktine AL, editores. Weight gain during pregnancy: reexamining the guidelines. Washington, DC: National Academies Press; 2009.

39 Coelho KS, Souza AI, Batista Filho M. Avaliação antropométrica do estado nutricional da gestante: visão retrospectiva e prospectiva. Rev Bras Saude Mater Infant 2002; 2(1):57-61.

40 Barros DC, Saunders C, Leal C. Avaliação nutricional antropométrica de gestantes brasileiras: uma revisão sistemática. Rev Bras Saude Mater Infant 2008; 8(4):363-376.^-4141 Padilha PDC, Accioly E, Veiga GV, Bessa TC, Libera BD. Nogueira JL, Alves PD, Souza Junior PR, Saunders C. The performance of various anthropometric assessment methods for predicting low birth weight in pregnant women. Rev Brasil Saude Mater Infant 2009; 9(2):197-206.. The Atalah et al.²⁰20 Atalah SE, Castillo LC, Castro SR, Aldea A. Propuesta de un nuevo estándar de evaluación nutricional en embarazadas. Rev Med Chil 1997; 125(12):1429-1436. nomogram can interpret high prevalence for the diagnosis of nutritional deficit/underweight, with lower sensitivity to identify overweight/obesity cases due to their adequate BMI range in the tenth gestational week (20.3 to 25.2 kg/m²), when compared with the other methods of anthropometric assessment of pregnant women⁴²42 Silva SL, Bresani-Salvi C, Caminha MFC, Figueroa JN, Batista Filho M. Classificação antropométrica de gestantes: comparação entre cinco métodos diagnósticos utilizados na América Latina. Rev Panam Salud Publica 2017; 41:e85..

The lack of an existing gold standard to define overweight and underweight in pregnancy hinders studies on the diagnostic accuracy of instruments based on the weight-height relationship, mainly due to the lack of specific curves for evaluating pregnant adolescents. Thus, the concern in the evaluation of pregnant adolescents is even more aggravated, since it refers to the convergence of two nutritional and metabolically critical situations, pregnancy and adolescence⁴³43 Canavan CR. Fawzi WW. Addressing Knowledge Gaps in Adolescent Nutrition: Toward Advancing Public Health and Sustainable Development. Curr Dev Nutr 2019; 3:7.^,4444 Das JK, Salam RA, Thornburg KL, Prentice AM, Campisi S, Lassi ZS, Koletzko B, Bhutta ZA. Nutrition in adolescents: physiology, metabolism, and nutritional needs. Ann NY Acad Sci 2017; 1393(1):21-33..

This study has some limitations that must be considered when assessing the results. First, health conditionality coverage data and, consequently, the percentage of pregnant women whose nutritional data were included in the information systems, are data for pregnant women in any age group, and not specific for pregnant adolescents, which may underestimate or overestimate the percentage of pregnant adolescents whose information was included in the system. Another relevant limitation is that prevalence levels were generated from the observations registered in the BFP Health Management System of the Ministry of Health, and were a sample of the universe of pregnant adolescent beneficiaries of the BFP, not allowing extrapolation to pregnant adolescents who are not beneficiaries of the program. Moreover, some SISVAN limitations should be considered. The system generates reports of data and information referring to the nutritional status as of 2008, which prevents the comprehensive evaluation of the trends of the nutritional status since the onset of the BFP in the beneficiary population. Finally, the tool used for the classification of nutritional status by the BFP was not developed for the population of pregnant adolescents, as previously discussed, but it is the tool indicated by the Ministry of Health for monitoring pregnant women in this age group.

One of the strengths of this study is that data represent the national outlook of the nutritional status of pregnant adolescents benefiting from the BFP, that is, all states and macro-regions were represented in this work. Also, we are unaware of other studies that aimed to determine the trend in the prevalence of nutritional deviations in this population in an assessment at the national level, which makes it the first study to outline the national setting of these conditions in pregnant adolescents who are beneficiaries of the BFP.

Conclusion

We can conclude that the prevalence of underweight among pregnant adolescents who are beneficiaries of the BFP had a decreasing trend in all Brazilian regions, while the prevalence of overweight and obesity shows an increasing trend throughout the country in the period. Finally, we highlight the importance of studies with methods identifying the determinants of pregnancy in adolescence and the change in the nutritional profile of this population to support the formulation of public policies aimed at this condition, given the repercussions of nutritional deviations at this stage of the life cycle and the unfavorable outcomes of pregnancy.

References

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