Anaemia in adolescent women: A priority for the nutrition agenda in Mexico. A comparison of data from the ENSANUT 2012 and 2018-2019 surveys.

The risk of anaemia in adolescence increases due to accelerated growth. This study aims to: (1) estimate the prevalence of anaemia in 2012 and 2018-2019 (Encuesta Nacional de Salud y Nutricion - ENSANUT [n = 5841 in 2012 and n = 2380 in 2018-2019]) in non-pregnant, Mexican adolescent women aged 12-19 years, and the changes in prevalence over this period according to sociodemographic, health and nutrition characteristics; (2) estimate the associations between anaemia and sociodemographic, health and nutrition characteristics in each year and overall, in non-pregnant Mexican adolescent women. Anaemia was defined as capillary haemoglobin <12 g/dL. The distribution of characteristics and their changes between 2012 and 2018-2019 were described. The covariate-adjusted prevalence of anaemia in 2012 and 2018-2019 and the changes over that period were estimated from a multiple log-binomial regression model and the factors associated with anaemia were assessed in each survey year and in both years combined. The prevalence of anaemia was 7.7% in 2012 and 13.1% in 2018-2019 (69% increase, Prevalence Ratio: PR = 1.69; 95%CI: 1.35, 2.13). The covariate-adjusted prevalence of anaemia increased from 6.9% to 10.5% in the overall population (PR = 1.53, 95%CI: 1.19, 1.96), and increased considerably in the age group 12-14 years (PR = 1.94, 95%CI: 1.36, 2.75), and in the northern region (PR = 3.68, 95%CI: 2.55, 5.32). Those receiving iron supplements or school breakfasts did not register a significant increase. A higher household wellbeing status and older age were associated with a lower prevalence of anaemia. Anaemia in non-pregnant adolescent women continues to be a public health problem. To improve the development and health of adolescent women in Mexico and to pave the way to a healthy pregnancy for the next generation, the causes of anaemia should be identified.