Neonatal Thyroid-stimulating Hormone Concentrations Research Articles

Does prenatal exposure to multiple airborne and tap-water pollutants increase neonatal thyroid-stimulating hormone concentrations? Data from the Picardy region, France

ObjectiveSystematic screening for congenital hypothyroidism by heel-stick sampling has revealed unexpected heterogeneity in the geographic distribution of newborn thyroid-stimulating hormone concentrations in Picardy, France. We explored a possible relationship with environmental pollutants. MethodsZip code geolocation data from mothers of newborns without congenital hypothyroidism born in 2021 were linked to ecological data for a set of airborne (particulate matter with a diameter of 2.5 μm or less [PM2.5] or 10 μm or less [PM10]) and tap-water (nitrate and perchlorate ions and atrazine) pollutants. Statistical associations between mean exposure levels during the third trimester of pregnancy and Thyroid-stimulating hormone (TSH) concentrations in 6249 newborns (51 % male) were investigated using linear regression models. ResultsMedian neonatal TSH concentration (interquartile range, IQR) was 1.7 (1–2.8) mIU/L. An increase of one IQR in prenatal exposure to perchlorate ions (3.6 μg/L), nitrate ions (19.2 mg/L), PM2.5 (3.7 μg/m3) and PM10 (3.4 μg/m3), were associated with increases in TSH concentrations of 2.30 % (95 % CI: 0.95–3.66), 5.84 % (95 % CI: 2.81–8.87), 13.44 % (95 % CI: 9.65–17.28) and 6.26 % (95 % CI: 3.01–9.56), respectively. ConclusionsPrenatal exposure to perchlorate and nitrate ions in tap water and to airborne PM over the third trimester of pregnancy was significantly associated with increased neonatal TSH concentrations.

Prenatal exposure to perfluorooctane sulfonate alternatives and associations with neonatal thyroid stimulating hormone concentration: A birth cohort study

BackgroundChlorinated polyfluorinated ether sulfonic acids (Cl-PFESA) and perfluorobutane sulfonate (PFBS), used as perfluorooctanesulfonate (PFOS) alternatives, were indicated as thyroid hormone disruptive toxicants in experimental studies. However, it is unclear whether prenatal exposure to Cl-PFESA and PFBS affects neonatal thyroid stimulating hormone (TSH) in human. ObjectiveTo disclose the relationships between prenatal Cl-PFESAs and PFBS exposure and neonatal thyroid-stimulating hormone (TSH) levels based on a perspective cohort study. MethodsA total of 1015 pairs of mother and newborn were included from an ongoing birth cohort study in Wuhan, China, between 2013 and 2014. Six PFASs in cord blood sera and TSH concentration in neonatal postpartum heel sticks blood were quantified. Mixed linear and weighted quantile sum (WQS) regression models were applied to assess the individual and combination effects of PFASs exposure on neonatal TSH levels with multiple covariates adjustments. ResultsAfter adjusting for potential confounders and other five PFASs, for each 1-ng/mL increase of PFBS or 8:2 Cl-PFESA, was negatively associated with 25.90% (95%CI: 37.37%, −12.32%; P < 0.001) and 27.19% (95%CI: 46.15%, −1.55%; P = 0.033) change in TSH in male but not female infants, respectively. No significant association was found between other PFASs exposure and neonatal TSH. Higher PFAS mixture in cord blood was significantly associated with decrease TSH concentration in all newborns (β = −0.36; 95%CI: 0.58, −0.13; P = 0.001) identified by WQS regression model. PFBS, PFOS and 6:2 Cl-PFESA were the major contributors to the neonatal TSH decrement with the weights of 56.50%, 18.71%, 12.81% among PFAS mixture, respectively.Conclusions: our prospective cohort study suggested a negative association of cord serum PFBS and 8:2 CI-PFESA with TSH concentration in newborns, especially for boys. Additional studies are required to elaborate on the underlying biological mechanisms, especially for PFBS.

Neonatal thyroid-stimulating hormone and association with attention-deficit/hyperactivity disorder.

Normal brain development is dependent on maternal, fetal and neonatal thyroid function. Measuring neonatal thyroid-stimulating hormone (TSH) 48-72 hours after birth screens for congenital hypothyroidism, allowing early treatment to avoid serious impairment. However, even within sub-clinical ranges, disrupted thyroid homeostasis during brain development has been linked to adverse neurodevelopmental outcomes, including attention-deficit/hyperactivity disorder (ADHD). To estimate the association between neonatal TSH below threshold for potential congenital hypothyroidism and subsequent ADHD diagnosis using a population-based birth cohort. Children with a diagnosis of ADHD in the Norwegian Mother, Father and Child Cohort Study (MoBa) were identified through linkage with the Norwegian Patient Registry using ICD-10 codes for hyperkinetic disorders. The study included 405 ADHD cases and 1,092 controls (born 2003-2008) with available neonatal TSH concentrations below 10 mU/L (cut-off for potential congenital hypothyroidism) measured in dried blood spots sampled 48-72 hours after birth. In multivariable, quintile models the relationship appeared to follow a U-shaped pattern with elevated odds ratios (OR) at lower and higher TSH levels. Among children with TSH in the lowest quintile, odds of ADHD was approximately 1.5-fold higher than children in the middle quintile (OR 1.60, 95% CI 1.09, 2.34), which was driven by substantially elevated risk among girls, with no association among boys (Pinteraction = 0.02; girls OR 3.10, 95% CI 1.53, 6.30; boys OR 1.16, 95% CI 0.73, 1.84). ADHD risk appeared to be elevated among newborns with low TSH levels (i.e. with hyperthyroid status), and this association was mainly found among girls. Because our findings are suggestive of increased risk at very low TSH concentrations, where analytical accuracy is low, future studies should employ highly sensitive assays capable of accurate quantitation at very low concentrations. Also, larger studies are needed to investigate these associations at higher neonatal TSH concentrations where data are more widely distributed.

Iodine status of Saint Petersburg adult residents

Обоснование. В мире около двух миллиардов человек имеют недостаточное потребление йода.&#x0D; Цель. Оценить обеспеченность йодом и эффективность профилактики йодного дефицита у взрослого населения Санкт-Петербурга.&#x0D; Методы. В ретроспективной части работы проведен анализ распространенности гипертиреотропинемии новорожденных Санкт-Петербурга за период 2013–2014 гг. В одномоментное поперечное когортное исследование были включены 542 жителя Санкт-Петербурга в возрасте 18–77 лет. Все участники были разделены на три группы согласно возрасту. Беременные женщины были выделены в отдельную группу. У всех участников проведено анкетирование и проанализированы значения йодурии.&#x0D; Результаты. Количество новорожденных, имевших концентрацию тиреотропного гормона более 5 мЕД/л, составило 6,9%, отражая дефицит йода легкой степени тяжести у населения. Йодированную соль использовали в пищу только 41,1% всех обследованных и 52,2% беременных женщин. Препараты йода принимала половина беременных женщин. Медиана йодурии (МЙУ) всех участников составила 91,2 мкг/л и соответствовала дефициту йода легкой степени тяжести. Значение МЙУ у беременных женщин составило 112,4 мкг/л и соответствовало недостаточному потреблению йода.&#x0D; Заключение. Население Санкт-Петербурга проживает в регионе легкого дефицита йода. Профилактика дефицита йода, проводимая в Санкт-Петербурге в 2013–2015 гг., недостаточно эффективна. Лица репродуктивного возраста и беременные женщины имеют дефицит йода легкой степени тяжести.

Association between borderline neonatal thyroid-stimulating hormone concentrations and educational and developmental outcomes: a population-based record-linkage study

Congenital hypothyroidism causes intellectual delay unless identified and effectively treated soon after birth. Newborn screening has almost eliminated intellectual disability associated with congenital hypothyroidism. However, clinical uncertainty remains about infants with thyroid-stimulating hormone (TSH) concentrations less than the newborn screening cutoffs. We assessed the association between neonatal TSH concentrations and educational and developmental outcomes. We did a population-based record-linkage study of all liveborn infants undergoing newborn screening from 1994 to 2008 in New South Wales, Australia, with assessments of childhood development or school performance. Very-low-birthweight babies (<1500 g) were excluded. Developmental and educational outcomes were obtained and these were linked to individual records by the New South Wales Centre for Health Record Linkage. The primary educational outcome was the proportion of students with National Assessment Program Literacy and Numeracy (NAPLAN) results lower than the national minimum standard in reading or numeracy measured at all ages, and the primary developmental outcome was the proportion of children who were classified as being developmentally high risk (vulnerable in two or more of the five developmental domains assessed by the Australian Early Development Census) at age 4-6 years. The proportions of infants with each outcome were calculated per percentile (0-100) of TSH concentration. Multivariable logistic regression was used to account for potential confounding by maternal and fetal variables known to affect neonatal TSH concentrations or neurodevelopmental outcomes. 503 706 infants had a neonatal TSH result that linked to a developmental or educational outcome. 149 569 infants born between 2002 and 2008 were linked to an Australian Early Development Census developmental outcome and 354 137 were linked to a NAPLAN educational outcome. Median follow-up for educational outcome was 10 years (IQR 8-12) and for developmental outcome was 5 years (5-6). 5·5% (14 137 of 257 752) of infants scored less than the national minimum standard for numeracy in percentiles lower than the 75th percentile and this increased with each increase of percentile group to 11·3% (15 of 133) of infants with a TSH concentration between the 99·90th and 99·95th percentile. Infants with a neonatal TSH concentration in the 99·95th percentile or higher (above newborn screening cutoff) and likely to have diagnosed and treated congenital hypothyroidism had similar results to infants with a TSH concentration lower than the 75th percentile for both educational and developmental outcomes. Infants with a neonatal TSH concentration between the 99·5th and 99·9th percentile were more likely to have special needs (adjusted odds ratio [aOR] 1·68, 95% CI 1·23-2·30), poor numeracy performance (aOR 1·57, 1·29-1·90), and developmentally high risk (aOR 1·52, 1·20-1·93). We found an association between neonatal TSH concentrations lower than the present newborn screening thresholds and poor educational and developmental outcomes. This association needs further investigation to assess whether assessment and treatment of these infants might improve their long-term cognitive outcomes. Australian National Health and Medical Research.

Neonatal thyroid-stimulating hormone concentration and psychomotor development at preschool age

ObjectiveThyroid hormones are essential for normal brain development. The aim of this study is to assess if high concentration of thyroid stimulating hormone (TSH) that is below the clinical threshold...

Neonatal thyroid-stimulating hormone level is influenced by neonatal, maternal, and pregnancy factors

The percentage of newborns with a neonatal whole blood thyroid-stimulating hormone (TSH) greater than 5 mIU/L has been used as an indicator of iodine deficiency at the population level. However, TSH levels in newborns may be influenced by many factors other than iodine status. The objective of this study was to identify neonatal, maternal, and pregnancy-related determinants of neonatal TSH levels in a retrospective cohort study. The study sample included 313 Belgian mothers and their 4- to 5-year-old children. The children had a neonatal TSH concentration between 0 and 15 mIU/L at neonatal screening, and blood samples were collected 3 to 5 days after birth. Children with suspected congenital hypothyroidism (neonatal TSH level >15 mIU/L), prematurely born (ie, <37 weeks), or with a low birth weight (ie, <2500 g) were excluded. Information about maternal and birth-related determinants was collected from the neonatal screening center via a self-administered questionnaire filled in by the mother together with the child's health booklet. Higher TSH levels were found in spring and winter compared to summer and autumn (P = .011). Higher TSH levels were associated with lifetime smoking behavior (up to child birth) in the mother (P = .005), lower weight gain during pregnancy (P = .014), and longer pregnancies (P = .003). This study showed that several neonatal, maternal, and pregnancy-related determinants are influencing neonatal TSH level.

Protocol of the PSYCHOTSH study: association between neonatal thyroid stimulating hormone concentration and intellectual, psychomotor and psychosocial development at 4-5 year of age: a retrospective cohort study.

BackgroundSeveral European countries, including Belgium, still suffer from mild iodine deficiency. Thyroid stimulating hormone (TSH) concentration in whole blood measured at birth has been proposed as an indicator of maternal iodine status during the last trimester of pregnancy. It has been shown that mild iodine deficiency during pregnancy may affect the neurodevelopment of the offspring. In several studies, elevated TSH levels at birth were associated with suboptimal cognitive and psychomotor outcomes among young children. This paper describes the protocol of the PSYCHOTSH study aiming to assess the association between neonatal TSH levels and intellectual, psychomotor and psychosocial development of 4–5 year old children. The results could lead to a reassessment of the recommended cut-off levels of 5 > mU/L used for monitoring iodine status of the population.MethodsIn total, 380 Belgian 4–5 year old preschool children from Brussels and Wallonia with a neonatal blood spot TSH concentration between 0 and 15 mU/L are included in the study. For each sex and TSH-interval (0–1, 1–2, 2–3, 3–4, 4–5, 5–6, 6–7, 7–8, 8–9 and 9–15 mU/L), 19 newborns were randomly selected from all newborns screened by the neonatal screening centre in Brussels in 2008–2009. Infants with congenital hypothyroidism, low birth weight and prematurity were excluded from the study. Neonatal TSH concentration was measured by the Autodelphia method in dried blood spots, collected by heel stick on filter paper 3 to 5 days after birth. Cognitive abilities and psychomotor development are assessed using the Wechsler Preschool and Primary Scale of Intelligence - third edition - and the Charlop-Atwell Scale of Motor coordination. Psychosocial development is measured using the Child Behaviour Check List for age 1½ to 5 years old. In addition, several socioeconomic, parental and child confounding factors are assessed.ConclusionsThis study aims to clarify the effect of mild iodine deficiency during pregnancy on the neurodevelopment of the offspring. Therefore, the results may have important implications for future public health recommendations, policies and practices in food supplementation. In addition, the results may have implications for the use of neonatal TSH screening results for monitoring the population iodine status and may lead to the definition of new TSH cut-offs for determination of the severity of iodine status and for practical use in data reporting by neonatal screening centres.

Factors influencing neonatal thyroid-stimulating hormone concentrations as a measure of population iodine status

The World Health Organization (WHO) has recommended measurement of neonatal thyroid-stimulating hormone (TSH) as a marker of population iodine status. A population is considered iodine sufficient when <3% of neonatal blood samples collected 3-4 days after birth have TSH concentrations >5 mIU/L. However, changes in technology and clinical practices have opened the WHO criteria to various interpretations. This study aimed to investigate the effects of time of sampling, weight, and sex on neonatal TSH concentrations by analyzing neonatal TSH data, based on the WHO criteria for population iodine sufficiency. We analyzed the Western Australian (WA) Newborn Screening Program records for 198,826 babies born in WA between 2005 and 2011, to determine the relationship between neonatal TSH concentrations and time of sampling, weight, and sex. The proportion of TSH results above the WHO cut-off was higher for samples collected 48-72 h after birth rather than later, for males, for birth weights below 2500 g, and when a cut-off of 5.0 mIU/L was used. Following changes in newborn screening protocols and earlier collection of blood samples, the WHO criteria appear inappropriate. We recommend that WHO revise current guidelines regarding use of neonatal TSH for monitoring population iodine status.

Neonatal Thyroid-Stimulating Hormone Concentrations in Belgium: A Useful Indicator for Detecting Mild Iodine Deficiency?

It has been proposed that neonatal thyroid-stimulating hormone (TSH) concentrations are a good indicator of iodine deficiency in the population. A frequency of neonatal TSH concentrations above 5 mU/L below 3% has been proposed as the threshold indicating iodine sufficiency. The objective of the present study was to evaluate feasibility and usefulness of nation-wide neonatal TSH concentration screening results to assess iodine status in Belgium. All newborns born in Belgium during the period 2009–2011 (n = 377713) were included in the study, except those suffering from congenital hypothyroidism and premature neonates. The frequency of neonatal TSH concentrations above 5 mU/L from 2009 to 2011 in Belgium fluctuated between 2.6 and 3.3% in the centres using the same TSH assay. There was a significant inverse association between neonatal TSH level and birth weight. The longer the duration between birth and screening, the lower the TSH level. Neonatal TSH levels were significantly lower in winter than in spring or autumn and significantly lower in spring and summer than in autumn while significantly higher in spring compared to summer. In conclusion, despite that pregnant women in Belgium are mildly iodine deficient, the frequency of neonatal TSH concentrations above 5 mU/L was very low, suggesting that the neonatal TSH threshold proposed for detecting iodine deficiency needs to be re-evaluated. Although neonatal TSH is useful to detect severe iodine deficiency, it should not be recommended presently for the evaluation of iodine status in mildly iodine deficient regions.

Increased iodine deficiency in Victoria, Australia: analysis of neonatal thyroid‐stimulating hormone data, 2001 to 2006

To use neonatal thyroid-stimulating hormone (TSH) concentration data to measure the iodine status of the population of the Australian state of Victoria. Retrospective analysis of the results of 368,552 neonatal heel-prick blood tests for TSH concentration in Victoria in the years 2001-2006. Iodine deficiency as indicated by a mean percentage of neonatal TSH concentrations > 5 mIU/L of over 3% in accordance with World Health Organization, United Nations Children's Fund and International Council for the Control of Iodine Deficiency Disorder criteria; comparison of findings for the nine Department of Human Services health regions in Victoria. The mean percentage of neonatal TSH concentrations > 5 mIU/L ranged from 4.07% in 2001 to 9.65% in 2006, and this increase was statistically significant (P < 0.001). The populations of all nine Victorian health regions showed increasing iodine deficiency over the study period. Metropolitan populations had higher iodine deficiency than non-metropolitan populations, and this difference was also statistically significant (P < 0.05). These results are consistent with urinary iodine excretion research in Victoria. The high percentage of elevated TSH concentrations among newborns is of concern and requires ongoing monitoring. Neonatal TSH assay is part of routine screening in Australia, and thus offers an effective and economical method of monitoring population iodine status.

Neonatal TSH screening: is it a sensitive and reliable tool for monitoring iodine status in populations?

Iodine deficiency is the most common cause of preventable brain damage in the newborn. The indicators for assessing iodine nutritional status include urinary iodine excretion, thyroid size, thyroid stimulating hormone (TSH) and thyroglobulin (Tg) concentrations in the blood. Neonatal TSH concentration is increased when the supply of thyroid hormone and iodine from the maternal circulation to the foetus has been compromised. The World Health Organization (WHO) has suggested that when a sensitive assay is used on samples collected 3-4 days after birth, a <3% frequency of TSH concentrations >5 mIUl(-1) indicates iodine sufficiency in a population. However, many studies have attempted to apply the frequency of neonatal TSH values >5 mIUl(-1) in determining population iodine status and monitoring intervention programmes, and although some have proven to be successful, most have provided conflicting or uncertain data. This is due to the many technical issues that remain unresolved on the use of neonatal TSH screening for monitoring iodine status, making it doubtful as a sensitive and reliable quantitative tool. More research is required to resolve these issues. In the interim, WHO should consider withdrawing its current guidelines for neonatal TSH screening for monitoring iodine deficiency in populations.

Maternal iodine status and neonatal thyroid-stimulating hormone concentration: a community survey in Songkhla, southern Thailand

To determine iodine intake and urinary iodine excretion (UIE) in a group of pregnant Thai women and the concentration of thyroid-stimulating hormone (TSH) in their neonates. A prospective cohort study. Three districts of Songkhla, southern Thailand. Two hundred and thirty-six pregnant women. A quarter of the participants lacked knowledge of iodine and the prevention of iodine deficiency, although 70 % used iodized salt. Those who did not use iodized salt stated that they had no knowledge about iodine (57 %) and no iodized salt was sold in their village (36 %). The median iodine intake in the three districts was 205-240 microg/d, with 53-74 % of pregnant women having iodine intake <250 microg/d. The median UIE in the three districts was 51-106 microg/l, with 24-35 % having UIE < 50 microg/l. The mean neonatal TSH was 2.40 (sd 1.56) mU/l, with 8.9 % of neonates having TSH > 5 mU/l. The studied women and their fetuses were at risk of mild iodine deficiency. About a quarter of the participants lacked knowledge of the importance of iodine. Education regarding the importance of iodine supplements and the promotion of iodized salt should be added to national health-care policies in order to prevent iodine-deficiency disorders, diseases that are subclinical but have long-term sequelae.

Embarazo y déficit de yodo. Situación actual

Several studies performed in Spain have reported iodine deficiency in pregnant women but data from Valencia are lacking. The aim of the present study was to determine the degree of implantation of iodine supplementation in pregnant women in our health area.A total of 232 pregnant women were studied in the first trimester of pregnancy. Thyroid-stimulating hormone (TSH), free thyroxine, and antiperoxidase antibodies were measured. A survey was performed on intake of iodized salt and pharmacological iodine supplements. Neonatal TSH concentrations were measured, based on screening of metabolopathies, in the newborns of participating women.Then mean age was 30.5+/-4.4 years. A total of 60.8% of the women consumed iodized salt, 51.3% took iodine polyvitamins and only 14.2% consumed potassium iodide. The median urinary iodine concentration was 100 microg/l; 66% had urinary iodine concentrations below the recommended level (150 microg/l). A positive association was found between pharmacological iodine intake and urinary iodine (p=0.016). Ten percent of the women had mild hypothyroxinemia, while 5.7% of the newborns had elevated TSH levels.Iodine intake in pregnant women in our health area is low, despite current recommendations. Our data support the need to promote the use of iodized salt in every home and to systematically administer potassium iodide supplements in all pregnant women.

Neonatal thyroid-stimulating hormone concentrations in northern Sydney: further indications of mild iodine deficiency?

To determine whether thyroid-stimulating hormone (TSH) concentrations in a large sample of neonates meet World Health Organization criteria for an iodine-replete population (< 3% of neonates with whole-blood TSH concentrations > 5 mlU/L), and, in a small subset of neonates, to examine the correlation between maternal urinary iodine and neonatal TSH concentrations. Cross-sectional study of neonatal whole-blood TSH values obtained as part of a routine newborn screening program. Royal North Shore Hospital (RNSH) in northern Sydney. Two anonymous samples of neonates born at RNSH (1316 infants born between August 1998 and April 1999 and 1457 infants born between 1 March and 31 December 2000); and 84 infants whose mothers had attended RNSH between September 1998 and August 1999 and supplied a urine sample for iodine measurement. Iodine status of neonates (proportion with whole-blood TSH values > 5 mlU/L), and urine iodine concentrations of pregnant women. In the two large population samples of neonates, 8.1% (95% CI, 6.6%-9.5%) and 5.4% (95% Cl, 4.3%-6.6%), respectively, had whole-blood TSH values > 5 mlU/L (prevalence range for mild thyroid deficiency, 3%-19%). Comparing the TSH values of the 1316 anonymous infants and the 84 identified infants showed no difference between the proportions with TSH values > 5 mlU/L (8.1% v 10.7%, respectively; P = 0.39). Urine iodine concentrations in the 84 pregnant women indicated borderline mild iodine deficiency. TSH values in their 84 infants were positively correlated with maternal urine iodine concentrations. Our results suggest that the population of northern Sydney may have mild iodine deficiency. However, the expected relationship between maternal urine iodine levels and neonatal TSH concentrations was not found.

Increased recall rate at screening for congenital hypothyroidism in breast fed infants born to iodine overloaded mothers.

Skin disinfection with povidine-iodine (PVP-I) is widely used in obstetrics. We evaluated the influence of PVP-I in mothers at delivery on the serum thyroid stimulating hormone concentrations of their infants at the time of screening for congenital hypothyroidism. The study covered 4745 infants who were either breast fed (3659, 77%) or bottle fed (1086, 23%); 3086 (65%) of them were born to mothers with no iodine overload (controls) and 1659 (35%) to mothers with iodine overload. Compared with the control group, the breast and bottle fed infants born to mothers with iodide overload had a shift of neonatal thyroid stimulating hormone concentration towards high values. The shift was maximal in the breast fed infants with a 25 to 30 fold increase in the recall rate at screening for congenital hypothyroidism (serum thyroid stimulating hormone greater than 50 mU/l) while in the bottle fed infants, the recall rate was barely modified. In conclusion, the use of PVP-I in mothers at delivery induces a transient impairment of thyroid function in their infants, especially if breast fed. This situation is detrimental to screening for congenital hypothyroidism. Consequently PVP-I is not recommended in obstetrics.