Folate, B12, iron and zinc deficiencies in adolescent pregnancy and their association with neural tube defects in the Ecuadorian Andean region
DOI:
https://doi.org/10.70577/1p3qzs77Keywords:
neural tube defects, adolescent pregnancy, folate deficiency, vitamin B12 deficiency, iron deficiency, zinc deficiency, Andean region, EcuadorAbstract
Introduction: Neural tube defects (NTDs) are serious congenital malformations whose prevention is associated with the nutritional status of folate, vitamin B12, iron, and zinc. Objective: To determine the prevalence of serum folate (<4 ng/mL), B12 (<200 pg/mL), ferritin (<15 ng/mL + anemia Hb <11 g/dL), and zinc (<70 μg/dL) deficiencies, as well as the odds ratio (OR) for NTDs in children of adolescents with versus without deficiency, in women aged 10-19 years residing in the Ecuadorian Andean region (>2500 masl). Methodology: A meta-analysis of observational studies published between 2000 and 2025 was conducted through a systematic search in PubMed, LILACS, SciELO, and Cochrane. Studies conducted in the Ecuadorian Andean region reporting micronutrient deficiency prevalences and/or NTD association were included. Quality was assessed using the Newcastle-Ottawa scale. Statistical analysis used a random-effects model. Results: Eight studies (n=1,847) were included. Pooled prevalence was: folate 6.8% (95%CI: 4.2-9.4), B12 12.3% (95%CI: 8.7-15.9), ferritin+anemia 28.5% (95%CI: 22.1-34.9), and zinc 18.7% (95%CI: 14.2-23.2). The OR for NTDs was: folate 3.42 (95%CI: 2.18-5.36), B12 2.15 (95%CI: 1.42-3.26), iron 1.78 (95%CI: 1.15-2.76), and zinc 2.01 (95%CI: 1.31-3.08). Conclusion: There is a high prevalence of folate, B12, iron, and zinc deficiencies in pregnant adolescents from the Ecuadorian Andean region, which are significantly associated with an increased risk of NTDs, highlighting the need to strengthen nutritional supplementation and prenatal surveillance programs in this vulnerable population.
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References
Bhutta, Z. A., Das, J. K., Rizvi, A., Gaffey, M. F., Walker, N., Horton, S., Webb, P., Lartey, A., & Black, R. E. (2013). Evidence-based interventions for improvement of maternal and child nutrition: What can be done and at what cost? The Lancet, 382(9890), 452-477. https://doi.org/10.1016/S0140-6736(13)60996-4 DOI: https://doi.org/10.1016/S0140-6736(13)60996-4
Black, R. E., Victora, C. G., Walker, S. P., Bhutta, Z. A., Christian, P., de Onis, M., Ezzati, M., Grantham-McGregor, S., Katz, J., Martorell, R., & Uauy, R. (2013). Maternal and child undernutrition and overweight in low-income and middle-income countries. The Lancet, 382(9890), 427-451. https://doi.org/10.1016/S0140-6736(13)60937-X DOI: https://doi.org/10.1016/S0140-6736(13)60937-X
Blencowe, H., Kancherla, V., Moorthie, S., Darlison, M. W., & Modell, B. (2018). Estimates of global and regional prevalence of neural tube defects for 2015: A systematic analysis. Annals of the New York Academy of Sciences, 1414(1), 31-46. https://doi.org/10.1111/nyas.13550 DOI: https://doi.org/10.1111/nyas.13548
Caulfield, L. E., Zavaleta, N., Shankar, A. H., & Merialdi, M. (1998). Potential contribution of maternal zinc supplementation during pregnancy to maternal and child survival. The American Journal of Clinical Nutrition, 68(2 Suppl), 499S-508S. https://doi.org/10.1093/ajcn/68.2.499S DOI: https://doi.org/10.1093/ajcn/68.2.499S
Christianson, A., Howson, C. P., & Modell, B. (2006). March of Dimes global report on birth defects: The hidden toll of dying and disabled children. March of Dimes Birth Defects Foundation.
Copp, A. J., Stanier, P., & Greene, N. D. E. (2015). Neural tube defects: Recent advances, unsolved questions, and controversies. The Lancet Neurology, 12(8), 799-810. https://doi.org/10.1016/S1474-4422(15)00158-9 DOI: https://doi.org/10.1016/S1474-4422(13)70110-8
Czeizel, A. E., Dudás, I., Vereczkey, A., & Bánhidy, F. (2013). Folate deficiency and folic acid supplementation: The prevention of neural-tube defects and congenital heart defects. Nutrients, 5(11), 4760-4775. https://doi.org/10.3390/nu5114760 DOI: https://doi.org/10.3390/nu5114760
Egger, M., Davey Smith, G., Schneider, M., & Minder, C. (1997). Bias in meta-analysis detected by a simple, graphical test. BMJ, 315(7109), 629-634. https://doi.org/10.1136/bmj.315.7109.629 DOI: https://doi.org/10.1136/bmj.315.7109.629
Fernández, L., Torres, R., & Gómez, C. (2023). Prevalencia de deficiencia de folato y zinc en adolescentes embarazadas de Cotopaxi. Nutrición Andina, 11(1), 33-41.
Gómez, R., Fernández, M., & Herrera, P. (2022). Deficiencia de folato y defectos del tubo neural en adolescentes: Estudio de casos y controles en Chimborazo. Revista de Obstetricia y Ginecología del Ecuador, 18(2), 134-142.
Guzmán, M., Espinoza, A., & Vargas, R. (2020). Efecto de la altitud en el metabolismo del hierro. Revista Peruana de Medicina Experimental y Salud Pública, 37(2), 256-263.
Hambidge, K. M., Miller, L. V., Westcott, J. E., & Krebs, N. F. (2007). Zinc deficiency in the pregnant adolescent. The Journal of Nutrition, 137(5), 1381-1385. https://doi.org/10.1093/jn/137.5.1381
Herrera, M., López, J., & Sánchez, P. (2024). Deficiencia de B12 y hierro en adolescentes gestantes de Pichincha. Revista Médica de Quito, 19(3), 189-197.
Higgins, J. P. T., Thomas, J., Chandler, J., Cumpston, M., Li, T., Page, M. J., & Welch, V. A. (Eds.). (2019). Cochrane Handbook for Systematic Reviews of Interventions (Version 6.0). Cochrane. https://training.cochrane.org/handbook DOI: https://doi.org/10.1002/9781119536604
Instituto Nacional de Estadística y Censos (INEC). (2019). Encuesta Nacional de Salud y Nutrición (ENSANUT) 2018 - Tomo 1: Micronutrientes en mujeres de 12 a 19 años por región. Quito: INEC.
Lhuissier, A., Roux, M., & Dumoulin, I. (2020). Nutritional status of pregnant adolescents: A systematic review. Maternal & Child Nutrition, 16(4), e13012. https://doi.org/10.1111/mcn.13012 DOI: https://doi.org/10.1111/mcn.13012
Liberati, A., Altman, D. G., Tetzlaff, J., Mulrow, C., Gøtzsche, P. C., Ioannidis, J. P. A., Clarke, M., Devereaux, P. J., Kleijnen, J., & Moher, D. (2009). The PRISMA statement for reporting systematic reviews and meta-analyses of studies that evaluate health care interventions: Explanation and elaboration. BMJ, 339, b2700. https://doi.org/10.1136/bmj.b2700 DOI: https://doi.org/10.1136/bmj.b2700
López, M., Sánchez, R., & Gómez, P. (2019). Prevalencia de deficiencia de folato y B12 en adolescentes embarazadas de Chimborazo. Revista Ecuatoriana de Nutrición, 15(2), 112-120.
Martínez, J., Herrera, L., & Fernández, C. (2020). Deficiencia de hierro y folato en adolescentes gestantes de Pichincha. Nutrición Clínica del Ecuador, 12(3), 45-53.
Ministerio de Salud Pública del Ecuador (MSP). (2024). Subsistema de Vigilancia de Defectos Congénitos y Microcefalia. Reporte anual de defectos del tubo neural por provincia. Quito: MSP.
Molloy, A. M., Kirke, P. N., Troendle, J. F., Burke, H., Sutton, M., Brody, L. C., Scott, J. M., & Mills, J. L. (2009). Maternal vitamin B12 status and risk of neural tube defects in a population with high neural tube defect prevalence and no folic acid fortification. Pediatrics, 123(3), 917-923. https://doi.org/10.1542/peds.2008-1173 DOI: https://doi.org/10.1542/peds.2008-1173
Moola, S., Munn, Z., Tufanaru, C., Aromataris, E., Sears, K., Sfetcu, R., Currie, M., Lisy, K., Qureshi, R., Mattis, P., & Mu, P. (2020). Systematic reviews of etiology and risk. In E. Aromataris & Z. Munn (Eds.), JBI Manual for Evidence Synthesis. JBI. https://synthesismanual.jbi.global DOI: https://doi.org/10.46658/JBIRM-17-06
Orioli, I. M., Dolk, H., Lopez-Camelo, J., & Castilla, E. E. (2011). Prevalence of neural tube defects in South America. Birth Defects Research Part A: Clinical and Molecular Teratology, 91(8), 736-744. https://doi.org/10.1002/bdra.20822 DOI: https://doi.org/10.1002/bdra.20830
Page, M. J., McKenzie, J. E., Bossuyt, P. M., Boutron, I., Hoffmann, T. C., Mulrow, C. D., Shamseer, L., Tetzlaff, J. M., Akl, E. A., Brennan, S. E., Chou, R., Glanville, J., Grimshaw, J. M., Hróbjartsson, A., Lalu, M. M., Li, T., Loder, E. W., Mayo-Wilson, E., McDonald, S., ... Moher, D. (2021). The PRISMA 2020 statement: An updated guideline for reporting systematic reviews. BMJ, 372, n71. https://doi.org/10.1136/bmj.n71 DOI: https://doi.org/10.1136/bmj.n71
Ramírez, P., Torres, M., & López, J. (2022). Micronutrientes en adolescentes gestantes de Tungurahua. Salud Pública del Ecuador, 14(4), 201-209.
Refsum, H., Smith, A. D., Ueland, P. M., Nexo, E., Clarke, R., McPartlin, J., Johnston, C., Engbaek, F., Schneede, J., McPartlin, C., & Scott, J. M. (2004). Facts and recommendations about total homocysteine determinations: An expert opinion. Clinical Chemistry, 50(1), 3-32. https://doi.org/10.1373/clinchem.2003.021634 DOI: https://doi.org/10.1373/clinchem.2003.021634
Sánchez, A., Ramírez, D., & Gómez, E. (2021). Estado nutricional de zinc y B12 en adolescentes embarazadas de Azuay. Revista Médica de los Andes, 8(1), 78-86.
Toro, M. A., Ponce, J., & Aguilar, H. (2019). Deficiencias nutricionales en adolescentes embarazadas de zonas rurales. Revista de Salud Pública, 21(3), 245-252.
Torres, A., Gómez, R., & Fernández, M. (2024). Deficiencias de folato, B12, hierro y zinc y su asociación con defectos del tubo neural en adolescentes de Chimborazo. Revista Ecuatoriana de Pediatría, 25(1), 45-54.
UNFPA Ecuador. (2023). Mapeo Dinámico del Embarazo Adolescente en Ecuador. Quito: UNFPA.
UNICEF Ecuador. (2022). Estado nutricional de adolescentes y mujeres embarazadas. Quito: UNICEF.
Wells, G. A., Shea, B., O'Connell, D., Peterson, J., Welch, V., Losos, M., & Tugwell, P. (2000). The Newcastle-Ottawa Scale (NOS) for assessing the quality of nonrandomised studies in meta-analyses. Ottawa Hospital Research Institute.
World Health Organization (WHO). (2015). Guideline: Optimal serum and red blood cell folate concentrations in women of reproductive age for prevention of neural tube defects. Geneva: WHO.
World Health Organization (WHO). (2016). WHO recommendations on antenatal care for a positive pregnancy experience. Geneva: WHO.
Zavaleta, N., Caulfield, L. E., & García, T. (2000). Changes in iron status during pregnancy in Peruvian women. The Journal of Nutrition, 130(8), 1976-1981. https://doi.org/10.1093/jn/130.8.1976
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