The Screening Of Thyroid Disease During The First Half Of Pregnancy And The Analysis Of The Test

Objective:To establish the trimester-specific reference range of thyroid function for the normal pregnant women during the first half of pregnancy.The prevalence rate of thyroid disease and the positive rate of TPOAb of pregnant women was evaluated.The comparison of serum TSH levels was maded on TPOAb positive women and TPOAb negative women.The relationship between different serum TSH levels and plasma glucose and lipid was analyzed. To better guide the clinical diagnosis and screening of thyroid disease.In order to provide basis for follow-up and necessary treatment on pregnant women with abnormal thyroid function.Methods:1.This study conducts a Cross-sectional study on 573 cases of pregnant women during the first half of pregnancy (1-20 weeks of gestation)from the maternity clinic in our hospital,starting from May 2013 to April 2014.By clinical epidemiological investigation, the data is collected. Serum thyroid stimulating hormone(TSH) and free triiodothyronine(FT3) and free thyroxine(FT4),thyroid peroxidase antibody(TPOAb), fasting plasma glucose(FPG), triglyceride(TG), total cholesterol(TC), high-density lipoprotein cholesterol(HDL-C) and low-density lipoprotein cholesterol(LDL-C) of these woman were detected.2.According to the standard established of by NACB, the thyroid function reference range was setted up during the first half of the pregnancy. The prevalence of thyroid disease was examined and compared with the prevalence of thyroid disease which examined according to the stangard by ATA. The serum TSH level is compared between TPOAb positive women and TPOAb negative women. According to our reference range, the relationship between different serum TSH levels and glucose and blood lipid was analyzed.3.The SPSS16.0 system is used to analyze the statistics data.The skewed distribution data are expressed with median.Comparison between non-normal distribution data is made using rank sum test.Numeration data is compared using the chi-square test and fisher’s precise test. Consistency check was made using Kappa test. A’P’value of less than 0.05 is considered to be statistically significant.Results:1.Established the reference ranges of thyroid function. In the first trimester:TSH 0.04-4.56mIU/L,FT3 3.66-6.18pmol/L,FT4 8.29-20.37pmol/L;At 13-20gestational weeks:TSH 0.05-5.75 mIU/L;FT3 3.57-5.74pmol/L,FT4 7.56-14.65pmol/L.2. According to the standards of ATA guidelines recommend,the total prevalence of maternal thyroid disorders during the first half of pregnancy was 22.51%. The occurrence of hyperthyroidism, subclinical hyperthyroidism, hypothyroidism, subclinical hypothyroidism and hypothyroxinemia was 4.19%,3.49%,1.05%,12.39% and 1.05%; The number of subclinial hypothyroidism is 55.04% in all pregnant women with thyroid disease. According to the standards of our hospital,the total prevalence of maternal thyroid disorders during the first half of pregnancy was 5.93%. The occurrence of hyperthyroidism, subclinical hyperthyroidism, hypothyroidism, subclinical hypothyroidism and hypothyroxinemia was 0.35%,1.4%,0.87%,1.57% and 1.75%.3.The total positive rate of TPOAb was 8.9%(51/573), the positive rate of TPOAb at 1-12 gestational weeks and 13-20 gestational weeks was 9.6%(38/396) and 7.34% (13/177). The serum TSH level of TPOAb positive pregnant women is significantly higher than that of TPOAb negative in the first trimester (P<0.05)4. Through the correlation analysis between the defferent serum TSH levels and pregnant women age, body mass index, blood pressure in the first half of pregnancy,it is no obvious difference on the pregnant women age, body mass index, blood pressure between the different serum TSH levels group (P>0.05).5. In the first trimester,the value of TC and LDL-C of pregnant women with the higher TSH levels is significantly higher than that of the normal TSH level group (P <0.05).Conclusions:1. It is statistically significant in the prevalence of thyroid disease between two diagnostic criteria. It can cause excessive diagnosis on screening gestational thyroid disease if we use the ATA guidelines standards.2.The incidence of subclinical hypothyroidism is highest in all thyroid disease during the first half of the pregnancy.3. It has a certain correlation between TPOAb positive and thyroid dysfunction. It is suggested that the serum TSH values of the TPOAb positive women need regular monitoring.4. Hypothyroidism and subclinical hypothyroidism can cause dyslipidemia. For patients with thyroid dysfunction, we need to follow-up plasma glucose ang lipid during pregnancy.