Mild iodine deficiency in women after spontaneous abortions living in an iodine-sufficient area of Czech Republic: prevalence and impact on reproductive health.

OBJECTIVE: Iodine deficiency is associated with thyroid dysfunction and adverse pregnancy outcomes. The aim of our study was to investigate the status of iodine saturation in women after spontaneous abortion (SpA) residing in an iodine-sufficient area and to evaluate their subsequent reproductive health. DESIGN: Nonrandomized prospective follow-up study. PATIENTS AND METHODS: We compared urinary iodine concentration (UIC) in 171 women 2-8 weeks (median 4) after an early SpA with age-matched controls. Women with known thyroid diseases were excluded. We also analysed a relationship of UIC to serum thyroid-stimulating hormone, free thyroxine, antibodies against thyroid peroxidase and thyroid ultrasound. Afterwards, we followed the women for a median of 38 months (range 12-47). We used a multivariate regression analysis to assess the influence of iodine status and other thyroid biochemical and ultrasound parameters on their subsequent reproductive health. RESULTS: Women after SpA were almost twice as likely to suffer from mild iodine deficiency and had lower median UIC as compared to age-matched controls [rate 105/181 (58·0%) vs 57/181 (31·5%), P < 0·001, medians UIC 92·00 vs 117·80 mcg/l, P < 0·001]. UIC was not influenced by the use of iodine supplements in the previous pregnancy. We did not find any association neither between UIC and thyroid dysfunction and/or thyroid antibodies, nor between UIC and rates of subsequent successful pregnancies or obstetric complications. CONCLUSIONS: More than half of women after SpA residing in an iodine-sufficient area are suffering from mild iodine deficiency. However, it does not seem to have a negative impact on their subsequent reproductive health.

Screening for autoimmune thyroid disorders after spontaneous abortion is cost-saving and it improves the subsequent pregnancy rate.

BACKGROUND: Hypothyroidism and/or autoimmune thyroid disorders (AITD) may contribute to spontaneous abortions (SpA). Cost-effectiveness analyses of thyroid screening in women after SpA are lacking. Our aim was to evaluate the cost-effectiveness of screening for AITD and/or hypothyroidism and their treatment in women after SpA with regard to their reproductive health. METHODS: We performed a cross-sectional non-randomized study with follow-up in 2008-2011 in the settings of Departments of Endocrinology and Obstetrics/Gynecology of a university hospital. We enrolled 258 women after SpA before the 12th gestational week and followed them for a median of 3 years. At enrollment, serum concentrations of thyroid stimulatory hormone (TSH), antibodies to thyroid peroxidase (TPOAb) and free thyroxine (FT4) were measured and thyroid ultrasound performed. Women with overt hypothyroidism were treated with levothyroxine (n = 45; 61.6%) and women with subclinical hypothyroidism or euthyroid AITD were treated (n = 28; 38.4%) or left untreated (n = 38; 14.7%). Euthyroid women without signs of AITD served as controls (n = 147; 57.0%). RESULTS: Of the 38 untreated women with AITD and/or subclinical hypothyroidism, 8 (21.1%) reported secondary infertility as compared to 16/147 (10.9%) controls and 3/73 (4.1%) treated women (p = 0.021). Treatment was associated with an increased rate of successfully completed subsequent pregnancies (increment of 6 newborns/100 women) and a savings of €19,539/100 women. Total costs per successfully completed pregnancy were €1,189 in controls, €1,564 in the treated, and €2,488 in the untreated women. CONCLUSIONS: Screening for thyroid disorders in women after SpA and treatment with levothyroxine is cost-saving and it improves the subsequent pregnancy rate.

Low concordance between positive antibodies to thyroperoxidase and thyroid ultrasound autoimmune pattern in pregnant women.

The diagnostic and prognostic role of thyroid ultrasound (TUS) in pregnant women positive for antibodies to thyroperoxidase (TPOAb) is unclear. The aim of our study was to compare the relation of ultrasound thyroid texture to the thyroid laboratory tests in pregnant women and controls. Using a semi-quantitative assessment we compared TUS in two groups of women with positive TPOAb and/or with thyroid dysfunction (TSH out of 0.06-3.67 mIU/L): 186 women in 1(st) trimester of pregnancy recruited from universal screening and 67 asymptomatic age-comparable non-pregnant non-postpartum women recruited from screening of general population (controls). Women with previous history of thyroid diseases were excluded. Only 64/131 (48.9 %) of TPOAb-positive pregnant women were TUS-positive (TUS with autoimmune pattern) in comparison with 35/49 (71.4 %) TPOAb-positive controls (p <0.011). Pregnant women had more often TSH >10.0 mIU/L if they were TPOAb-positive/TUS-positive as compared to those TPOAb-positive/TUS-negative (8/64 (12.5 %) vs. 0/67 (0 %), p = 0.009). The prevalence of preterm deliveries among TPOAb-positive women was significantly lower if TPOAb-positivity was not accompanied by TUS-positivity (2/67 (3.0 %) vs. 10/64 (15.6 %) in TPOAb-positive/TUS-positive women, p = 0.028). In conclusion, nearly half of the TPOAb-positive pregnant women did not have an autoimmune pattern in TUS. Normal TUS image in TPOAb-positive pregnant women might be a protective factor for preterm delivery.

The production of mannan-binding lectin is dependent upon thyroid hormones regardless of the genotype: a cohort study of 95 patients with autoimmune thyroid disorders.

Complement mannan-binding lectin (MBL) deficiency is associated with increased susceptibility to infections and autoimmune diseases. Previous studies suggested that the production of MBL is stimulated by thyroid hormones. The aim of our study was to investigate this association in patients with autoimmune thyroid diseases (AITD). Serum levels of MBL and parameters of the thyroid function were determined in 62 patients with Hashimoto's thyroiditis, 33 with Graves' disease and 47 blood donors. Follow-up measurements were performed after 6 to 24 months. MBL2 genotypes were determined using multiplex PCR and compared to 359 healthy Czech individuals. Serum levels of MBL tightly correlated with thyroid hormones, leading to strongly increased MBL levels in hyperthyroidism and decreased levels in hypothyroidism. With normalization of the thyroid function during follow-up, MBL levels decreased or increased respectively. The observed correlations were not due to MBL polymorphisms since the frequency of MBL2 polymorphisms in AITD patients was not different from the general population. We conclude that AITD are not associated with MBL polymorphisms. However, the MBL production is strongly dependent on thyroid function, regardless of the genotype.

Association between low levels of Mannan-binding lectin and markers of autoimmune thyroid disease in pregnancy.

Functional deficiency of mannan-binding lectin (MBL) has been associated with adverse pregnancy outcome. Adverse events during pregnancy have also been described in women with autoimmune thyroid diseases (AITD), and thyroid hormones have been shown to influence serum levels of MBL. Therefore, the aim of this study was to analyse the impact of MBL-deficiency on the outcome of pregnancy in relation to the presence of AITD. Almost one year after delivery, we assessed serum MBL levels and MBL2-genotypes in 212 women positively screened for AITD in pregnancy. In 103 of these women, we could also measure MBL levels in frozen serum samples from the 9-12(th) gestational week, obtaining 96 pairs of MBL values (pregnancy vs. follow-up). As controls, 80 sera of pregnant women screened negatively for AITD were used. MBL2-genotyping was performed using multiplex PCR. Women with thyroid dysfunction and/or thyroid peroxidase antibodies (TPOAb) had lower MBL levels during pregnancy than controls, (3275 vs. 5000 ng/ml, p<0.05). The lowest levels were found in women with elevated thyroid-stimulating hormone (TSH) levels in the absence of TPOAb (2207 ng/ml; p<0.01 as compared to controls). MBL2 genotype distribution did not differ between subgroups. At a median follow-up period of 17 months (range: 3-78 months) after delivery, median MBL level had decreased further to 1923 ng/ml (p<0.0001) without significant changes in TSH. In an explorative survey, functional MBL-deficiency was neither linked to a history of spontaneous abortion, nor other obstetric complications, severe infections throughout life/pregnancy or antibiotics use in pregnancy. In conclusion, hypothyroidism during pregnancy is associated with decreased MBL levels, and the levels decreased further after delivery.

Is age a risk factor for hypothyroidism in pregnancy? An analysis of 5223 pregnant women.

CONTEXT: The guidelines of American Thyroid Association from 2011 include age over 30 as one of the risk factors for hypothyroidism in pregnancy. OBJECTIVE: Our objective was to verify whether age increases the risk of autoimmune thyroid disease in pregnancy. DESIGN: We performed a cross-sectional study in 2006-2008 with laboratory assessment in a single center using primary care gynecological ambulances in cooperation with a referral center. PATIENTS: The study included 5223 consecutive pregnant women in gestational wk 9-12. MAIN OUTCOME MEASURE: We assessed the occurrence of pathological serum concentrations of TSH and/or antibodies against thyroperoxidase (TPOAb) with regard to age. Reference interval for TSH was 0.06-3.67 mU/liter; the upper cutoff value for TPOAb was 143 kU/liter. RESULTS: Overall, 857 women (16.4%) were positively screened. Of these, 294 (5.63%) had TSH elevation, 146 (2.79%) had TSH suppression, 561 (10.74%) were TPOAb positive, and 417 (7.98%) were euthyroid and TPOAb positive. The average age of women was 31.1 yr. The prevalence of hypothyroidism was 5.5 and 5.8% in women aged 30 or older and those under 30 yr, respectively (P value nonsignificant). Using a logistic regression model, we didn't find any significant association between age and serum TSH suppression, TSH elevation, or TPOAb positivity (P = 0.553, P = 0.680, and P = 0.056, respectively) or between age and TSH elevation with TPOAb positivity (P = 0.967). In a subgroup analysis of risk factors for hypothyroidism in 132 hypothyroid women, addition of age 30 or older increased the proportion of women identified in a case-finding screening strategy from 55.3 to 85.6%. CONCLUSIONS: Prevalence of autoimmune thyroid disease does not increase with age in pregnant women; however, addition of age 30 or over to the case-finding screening strategy may substantially improve its efficiency due to a larger number of women screened.