A Study On The Relationship Between Thyroid Dysfunction And Iodine Nutrition In Early Pregnancy And The Relationship Between Thyroid Dysfunction And Pregnancy Outcome

Objective In this study,firstly,we evaluate the iodine nutritional status about early pregnant women in Baotou,Inner Mongolia.Secondly,to evaluate the influence of different iodine nutritional status on thyroid function during pregnancy.Thirdly,to study the effects of clinical hypothyroidism,simple subclinical hypothyroidism,simple hypothyroidemia,and simple TPO-Ab(+)results on pregnancy outcomes in early pregnant women.Methods This study is divided into 2parts,the first part:To analyze the iodine nutrition status of pregnant women in the early pregnancy,we selected 600 pregnant women(6-10 weeks pregnant)who lived in baotou for at least 5 years from February 2019 to August 2019 were selected to measure urinary iodine level and thyroid function,and study whether there is statistical effect on the prevalence of thyroid disease in patients with iodine deficiency group(UIC<150ug/L),iodine beyond appropriate group(250ug/L?UIC<500ug/L),iodine excess group(UIC?500ug/L)and iodine appropriate group(150ug/L?UIC<250ug/L),respectively;The second part:A retrospective analysis in January 2018 to July 2019 in our hospital outpatient regular prenatal and abnormal thyroid function of patients in hospital childbirth medical records(diagnosis and management according to the guidelines of“2017 Guidelines of the American Thyroid Association for the Diagnosis and Management of Thyroid Disease During Pregnancy and the Postpartum”.Research groups include early pregnancy diagnosed clinical hypothyroidism 32 cases(group A),simple subclinical hypothyroidism 34cases(group B),simple hypothyroidemia 31 cases(group C)and simple TPO-Ab(+)33 cases(group D).The control group was normal thyroid function group 120 cases(group E).We compare the pregnancy outcome between research groups and control group.Results 1.The median urinary iodine of 600 pregnant women was174.46ug/L,which was generally in an appropriate state of iodine,but only accounted for 41.2%in the appropriate group,and 58.8%in the abnormal group(38.0%in the iodine deficiency group,18.5%in the iodine beyond appropriate group,and 2.3%in the iodine excess group).2.Iodine deficiency and the appropriate group TPO-Ab positive prevalence of comparative difference was statistically significant(c~2=3.94,p=0.047).We compare the iodine beyond appropriate group with the appropriate group,there is no significant difference.And we compare with the iodine excess group with the appropriate group,there is no significant difference too.But We compare the total iodine nutrition abnormality group with the appropriate group,found that the prevalence of subclinical hypothyroidism was significantly higher than that of iodine appropriate group(c~2=4.08,p=0.043).3.The incidence of threatened abortion in the pregnancy clinical hypothyroidism group was(31.25%)significantly higher than that in the normal group(10.83%),the difference was statistically significant(c~2=5.51,p=0.019).4.The incidence of threatened abortion in the pregnancy group with simple TPO-Ab(+)was significantly higher than that of the normal group,and the difference was statistically significant(c~2=3.94,p=0.047).5.There was a significant difference of the incidence of hypertensive disorders between pregnancy in simple subclinical hypothyroidism group and the normal group(23.52%vs 8.33%)(c~2=4.37,p=0.037),and the incidence of gestational diabetes mellitus(GDM)was 26.47%vs 10.0%,with a statistically significant difference(c~2=4.31,p=0.038).6.There was no significant difference in the incidence of premature delivery,low birth weight infant and premature rupture of membranes between each research group and the normal group.Conclusion This study showed that the overall level of urinary iodine in early pregnancy women in baotou was in an appropriate state of iodine,but the rate of iodine nutritional abnormality was more than half of the total,and iodine deficiency was widespread.Abnormal iodine nutrition in early pregnancy affects thyroid function.The prealence of HDP and GDM increased in early pregnancy with simple subclinical hypothyroidism.The incidence of TPO-Ab(+)threatened abortion in early pregnancy increased.The incidence risk of threatened abortion in clinical hypothyroidism is higher.It is recommended to check urinary iodine and thyroid function before pregnancy,and to consider pregnancy after adjustment to an appropriate state.