Endocrine Abstracts

Introduction: Iodine supplementation is recommended for populations at risk in countries without sufficient iodized salt coverage, as Portugal. Pregnancy is a time of particular susceptibility to malnutrition. In Portugal, despite the recommendation (issued in 2013 by the health authorities) to supplement iodine during preconception, pregnancy and lactation, pregnant women are still iodine deficient.

Objectives: To characterize the nutritional composition of prenatal supplements regarding iodine, iron, selenium, and folic acid. To evaluate iodine availability from iodine-containing supplement sales in Portuguese pharmacies. To assess iodine supplementation coverage from pharmacy dispenses.

Methods: Data from iodine supplement sales since 2008 in Portuguese pharmacies was provided by CEFAR-ANF (Centre for Health Evaluation and Research, National Association of Pharmacies). Product information was complemented with INFOMED (human medicinal products database) and Web search. Iodine, folic acid, and iron content was obtained through the label information. Pharmacy dispenses of iodine supplements between 2019 and 2021 were collected from a sample of female consumers, identified with at least one prescription associated to one fiscal number.

Results: Iodine-containing supplements represented 72% of prenatal supplement sales in 2023. Of 30 identified prenatal supplements, only 67% have the recommended iodine content. All the iodine-containing supplements also have folic acid, 87% iron and 83% selenium. Units of iodine-containing supplements sold increased over the years from 2008 (F(1,12)=211, P < 0.001, R2=0.94). When considering all sales (pharmacies and outside pharmacies [(that represent 11% total sales)]), the amount of iodine available from prenatal supplements reached 114 mg per birth, per day. From a sample of 86012 women with pharmacy dispenses between 2019 and 2021, mean duration of supplementation was 4.5 months (sd=3.8). Less than one percent is covered for the advisable period of 18 months.

Conclusion: Iodine-containing supplements represent a considerable percentage of prenatal supplement sales aligning with the usage reports by pregnant women in the literature. However, estimated duration of supplementation is below recommendations. These findings are in accordance with reported urinary iodine levels in the Portuguese pregnant population, prompting studies evaluating compliance, and verifying nutritional composition. Additional measures are needed for the promotion of women adherence to recommendations, to incite healthcare professionals to inform on iodine relevance, and for health authorities to implement policies to ensure iodine sufficiency to the population (universal salt iodization).