Prevalence of thyroid deficiency in pregnant women.
ABSTRACT The present study was designed to determine the current prevalence of gestational hypothyroidism, since maternal thyroxine deficiency is associated with poor obstetric outcomes and mental retardation in the surviving offspring.
TSH concentrations were measured in the sera of women at 15-18 weeks of gestation. Those sera with TSH concentrations above 6 mU/l and the two sera closest in order with TSH concentrations below 6 mU/l were further analysed for T4, FT4, TBG, and antithyroid antibodies. Study criteria for hypothyroidism were sera with elevated concentrations of TSH plus both a free T4 concentration and a total T4 concentration and/or T4/TBG ratio more than two standard deviations below the mean for the control pregnant women.
The sera were from 2000 consecutive women in Maine being tested for alpha-fetoprotein concentration at 15-18 weeks of gestation.
TSH concentrations above 6 mU/l were found in the sera of 49 women, 2.5% of the pregnant women. Six women with elevated TSH concentrations (range 6.9-54 mU/l) had both a FT4 concentration and a T4/TBG ratio and/or a T4 concentration more than two standard deviations below the respective control means, meeting the study criteria for thyroid deficiency, and thus giving a prevalence of 0.3%. The remaining 43 women with elevated TSH concentrations were classified as having compensated thyroid disease although some may have been hypothyroid. Fifty-eight per cent of women with TSH concentrations above 6 mU/l and 90% of the women with elevated TSH concentrations and at least one thyroxine index more than two standard deviations below the control means had positive titres of antithyroid antibodies as opposed to 11% of the controls.
Although it is not known what severity of maternal thyroid deficiency is necessary to cause fetal brain damage, the present data indicate a sufficiently high prevalence of thyroid dysfunction to demand investigation of the mental development of the offspring of women with thyroid dysfunction and of the effect of replacement therapy.
SourceAvailable from: Creswell J Eastman
[Show abstract] [Hide abstract]
ABSTRACT: The developmental toxicity of PCA was characterized and compared to PCP using a zebrafish model.•The developmental toxicity of PCA was at least 100 times lower than that of PCP.•PCP decreased T4 and increased T3 in the embryo but not PCA.•PCP increased expression of SYN, Dio3, THRαa and THRβ changes but decreased expression of Dio2.Ecotoxicology and Environmental Safety 02/2015; 112. DOI:10.1016/j.ecoenv.2014.10.004 · 2.48 Impact Factor
[Show abstract] [Hide abstract]
ABSTRACT: Objective: To determine the importance of screening for Thyriod disorders in the first trimester of pregnancy. Materials and Methods: The Study was conducted on 305 patients which were were randomly selected and screened on OPD basis by TSH levels (cut off level 0.10-2.50 mIU/ml). Results: In the 305 women screened mean age was 24.46 years, mean gestational age was 9.09 weeks, 89.83% were euthyroid, 9.8%were hypothyroid, 0.32% were hyperthyroid. Incidence of hypothyroidism in high risk population was 20.58% and in normal population was 6.7%. There was significant association of thyroid disorders with high risk factors (P < 0.001). In hypothyroid women 46% had adverse perinatal outcomes and 53.33% had normal outcomes. This shows statistically significant association abnormal TSH values with adverse pregnancy outcomes (P < 0.001). In abnormal perinatal outcomes 6.2% women had Caesarean section out of them 73.68% were euthyroid, 26.31% were hypothyroid 1.9% had preterm labour, out of them 50% were euthyroid, 50% were hypothyroid. Out of 2.2% spontaneous abortions 28.5% were in euthyroid group while 71.4% were in hypothyroid group. There was 1 term stillbirth in hypothyroid group. This study showed significant association between abnormal thyroid stimulating hormone (TSH) values and adverse perinatal outcomes (P < 0.001). Conclusion: There is significant correlation between risk factors and hypothyroidism. So high risk screening is mandatory in early pregnancy. But if we screen only high risk population we would miss 4.6% cases which could have been diagnosed and treated earlier. Therefore it is important to screen all pregnant women in the first trimester, it should be made mandatory.09/2014; 18(5):735-8. DOI:10.4103/2230-8210.139221