https://www.thelancet.com/pdfs/journals/lancet/PIIS0140-6736(13)60937-X.pdf

Maternal and child undernutrition and overweight in low-income and middle-income countries

Background: Thyroid disease in pregnancy is a common clinical problem. Since the guidelines for the management of these disorders by the American Thyroid Association (ATA) were first published in 2...

https://www.thyca.org/download/document/486/PregnancyandPostpartum.pdf

2017 Guidelines of the American Thyroid Association for the Diagnosis and Management of Thyroid Disease During Pregnancy and the Postpartum

Objective: The aim was to update the guidelines for the management of thyroid dysfunction during pregnancy and postpartum published previously in 2007. A summary of changes between the 2007 and 2012 version is identified in the Supplemental Data (published on The Endocrine Society's Journals Online web site at http://jcem.endojournals.org). Evidence: This evidence-based guideline was developed according to the U.S. Preventive Service Task Force, grading items level A, B, C, D, or I, on the basis of the strength of evidence and magnitude of net benefit (benefits minus harms) as well as the Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) system to describe both the strength of recommendations and the quality of evidence. Consensus Process: The guideline was developed through a series of e-mails, conference calls, and one face-to-face meeting. An initial draft was prepared by the Task Force, with the help of a medical writer, and reviewed and commented on by members of The Endocri...

/pdf/management-of-thyroid-dysfunction-during-pregnancy-and-575y0c8uhf.pdf

Management of Thyroid Dysfunction during Pregnancy and Postpartum: An Endocrine Society Clinical Practice Guideline

Pregnancy has a profound impact on the thyroid gland and thyroid function. The gland increases 10% in size during pregnancy in iodine-replete countries and by 20%– 40% in areas of iodine deficiency. Production of thyroxine (T4) and triiodothyronine (T3) increases by 50%, along with a 50% increase in the daily iodine requirement. These physiological changes may result in hypothyroidism in the later stages of pregnancy in iodine-deficient women who were euthyroid in the first trimester. The range of thyrotropin (TSH), under the impact of placental human chorionic gonadotropin (hCG), is decreased throughout pregnancy with the lower normal TSH level in the first trimester being poorly defined and an upper limit of 2.5 mIU/L. Ten percent to 20% of all pregnant women in the first trimester of pregnancy are thyroid peroxidase (TPO) or thyroglobulin (Tg) antibody positive and euthyroid. Sixteen percent of the women who are euthyroid and positive for TPO or Tg antibody in the first trimester will develop a TSH that exceeds 4.0 mIU/L by the third trimester, and 33%–50% of women who are positive for TPO or Tg antibody in the first trimester will develop postpartum thyroiditis. In essence, pregnancy is a stress test for the thyroid, resulting in hypothyroidism in women with limited thyroidal reserve or iodine deficiency, and postpartum thyroiditis in women with underlying Hashimoto’s disease who were euthyroid prior to conception. Knowledge regarding the interaction between the thyroid and pregnancy/the postpartum period is advancing at a rapid pace. Only recently has a TSH of 2.5 mIU/L been accepted as the upper limit of normal for TSH in the first trimester. This has important implications in regards to interpretation of the literature as well as a critical impact for the clinical diagnosis of hypothyroidism. Although it is well accepted that overt hypothyroidism and overt hyperthyroidism have a deleterious impact on pregnancy, studies are now focusing on the potential impact of subclinical hypothyroidism and subclinical hyperthyroidism on maternal and

/pdf/guidelines-of-the-american-thyroid-association-for-the-1oqnx3mmj9.pdf

Guidelines of the American Thyroid Association for the Diagnosis and Management of Thyroid Disease During Pregnancy and Postpartum The American Thyroid Association Taskforce on Thyroid Disease During Pregnancy and Postpartum

https://endoinfo.ru/guidelines/ata_hypothyroidism_adults.pdf

Clinical Practice Guidelines for Hypothyroidism in Adults: Cosponsored by the American Association of Clinical Endocrinologists and the American Thyroid Association

Salt iodization has been introduced in many countries to control iodine deficiency. Our aim was to assess global and regional iodine status as of 2011 and compare it to previous WHO estimates from 2003 and 2007. Using the network of national focal points of the International Council for the Control of Iodine Deficiency Disorders as well as a literature search, we compiled new national data on urinary iodine concentration (UIC) to add to the existing data in the WHO Vitamin and Mineral Nutrition Information System Micronutrients Database. The most recent data on UIC, primarily national data in school-age children (SAC), were analyzed. The median UIC was used to classify national iodine status and the UIC distribution to estimate the number of individuals with low iodine intakes by severity categories. Survey data on UIC cover 96.1% of the world’s population of SAC, and since 2007, new national data are available for 58 countries,including Canada, Pakistan, the UK, and the US. At the national level, there has been major progress: from 2003 to 2011, the number of iodine-deficient countries decreased from 54 to 32 and the number of countries with adequate iodine intake increased from 67 to 105. However, globally, 29.8% (95% CI = 29.4, 30.1) of SAC (241 million) are estimated to have insufficient iodine intakes. Sharp regional differences persist; southeast Asia has the largest number of SAC with low iodine intakes (76 million) and there has been little progress in Africa, where 39% (58 million) have inadequate iodine intakes. In summary, although iodine nutrition has been improving since 2003, global progress may be slowing. Intervention programs need to be extended to reach the nearly one-third of the global population that still has inadequate iodine intakes. J. Nutr. doi: 10.3945/jn.111.149393.

/pdf/global-iodine-status-in-2011-and-trends-over-the-past-decade-1wvuf65p2q.pdf

Global Iodine Status in 2011 and Trends over the Past Decade

The Consultation reached a general consensus on several important issues. First, that universal salt iodisation‡ (USI) remains the key strategy to eliminate iodine deficiency disorders. Second, that where USI has been effective for at least 2 years, with salt adequately iodised and consumed by more than 90% of the population 1 , it can be reasonably expected that the iodine needs of women of child-bearing age and pregnant and lactating women are covered by their diet, and that the iodine stored in the thyroid gland is sufficient to ensure adequate hormone synthesis and secretion. Third, that iodised salt may not provide enough iodine to meet a child’s needs during complementary feeding, especially if the mother is only marginally iodine sufficient, unless complementary foods are fortified with iodine. It may be necessary therefore to give additional iodine to makesure that requirements are met until such time as the child starts to eat the normal family food. Finally, there was consensus that monitoring of both iodised salt quality and iodine nutrition are important to ensure that an optimal state of iodine nutrition is reached and then sustained. The Consultation made several specific recommendations concerning requirements, indicators and strategies to control iodine deficiency disorders in pregnant and lactating women, and in children less than 2-years-old.

/pdf/prevention-and-control-of-iodine-deficiency-in-pregnant-and-532sn866rz.pdf

Prevention and control of iodine deficiency in pregnant and lactating women and in children less than 2-years-old: conclusions and recommendations of the Technical Consultation

Iodine status has been historically assessed by palpation of the thyroid and reported as goiter rates. Goiter is a functional biomarker that can be applied to both individuals and populations, but it is subjective. Iodine status is now assessed using an objective biomarker of exposure, i.e., urinary iodine concentrations (UICs) in spot samples and comparison of the median UIC to UIC cut-offs to categorize population status. This has improved standardization, but inappropriate use of the crude proportion of UICs below the cut-off level of 100 µg/L to estimate the number of iodine-deficient children has led to an overestimation of the prevalence of iodine deficiency. In this review, a new approach is proposed in which UIC data are extrapolated to iodine intakes, adjusted for intraindividual variation, and then interpreted using the estimated average requirement cut-point model. This may allow national programs to define the prevalence of iodine deficiency in the population and to quantify the necessary increase in iodine intakes to ensure sufficiency. In addition, thyroglobulin can be measured on dried blood spots to provide an additional sensitive functional biomarker of iodine status.

/pdf/assessment-of-iodine-nutrition-in-populations-past-present-525lw0ii7t.pdf

Assessment of iodine nutrition in populations: past, present, and future.

Background. Iodine deficiency is a global public health problem, and estimates of the extent of the problem were last produced in 2003. Objectives. To provide updated global estimates of the magnitude of iodine deficiency in 2007, to assess progress since 2003, and to provide information on gaps in the data available. Methods. Recently published, nationally representative data on urinary iodine (UI) in school-age children collected between 1997 and 2006 were used to update country estimates of iodine nutrition. These estimates, alongside the 2003 estimates for the remaining countries without new data, were used to generate updated global and regional estimates of iodine nutrition. The median UI was used to classify countries according to the public health significance of their iodine nutrition status. Progress was measured by comparing current prevalence figures with those from 2003. The data available for pregnant women by year of survey were also assessed. Results. New UI data in school-age children were available for 41 countries, representing 45.4% of the world’s school-age children. These data, along with previous country estimates for 89 countries, are the basis for the estimates and represent 91.1% of this population group. An estimated 31.5% of school-age children (266 million) have insufficient iodine intake. In the general population, 2 billion people have insufficient iodine intake. The number of countries where iodine deficiency is a public health problem is 47. Progress has been made: 12 countries have progressed to optimal iodine status, and the percentage of school-age children at risk of iodine deficiency has decreased by 5%. However, iodine intake is more than adequate, or even excessive, in 34 countries: an increase from 27 in 2003. There are insufficient data to estimate the global prevalence of iodine deficiency in pregnant women. Conclusions. Global progress in controlling iodine deficiency has been made since 2003, but efforts need to be accelerated in order to eliminate this debilitating health issue that affects almost one in three individuals globally. Surveillance systems need to be strengthened to monitor both low and excessive intakes of iodine.

https://journals.sagepub.com/doi/pdf/10.1177/156482650802900305

Iodine deficiency in 2007: global progress since 2003.

Background: Dietary iodine intake is required for the production of thyroid hormone. Consequences of iodine deficiency include goiter, intellectual impairments, growth retardation, neonatal hypothyroidism, and increased pregnancy loss and infant mortality. Summary: In 1990, the United Nations World Summit for Children established the goal of eliminating iodine deficiency worldwide. Considerable progress has since been achieved, largely through programs of universal salt iodization. Approximately 70% of all households worldwide currently have access to adequately iodized salt. In 2013, as defined by a national or subnational median urinary iodine concentration of 100–299 μg/L in school-aged children, 111 countries have sufficient iodine intake. Thirty countries remain iodine-deficient; 9 are moderately deficient, 21 are mildly deficient, and none are currently considered severely iodine-deficient. Ten countries have excessive iodine intake. In North America, both the United States and Canada are generally ...

Maria Andersson

Papers

Global Iodine Status in 2011 and Trends over the Past Decade

Prevention and control of iodine deficiency in pregnant and lactating women and in children less than 2-years-old: conclusions and recommendations of the Technical Consultation

Assessment of iodine nutrition in populations: past, present, and future.

Iodine deficiency in 2007: global progress since 2003.

Global iodine nutrition: Where do we stand in 2013?