Registry Study for Pregnant Women With Iodine Overload

Study Overview
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Brief Summary
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Pre-gestational performance of hysterosalpingography (HSG) using an oil-soluble iodinated contrast medium has been demonstrated to be the main cause of excessive iodine exposure for pregnant women. However, its long-term health effects on the mothers and offsprings have not been adequately elucidated. A case registry study is designed to follow up all the pregnant women with pre-gestational history of ethiodized-oil HSG examination and try to keep track of maternal and fetal outcomes.

Official Title
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Registry Study on Effect of Excessive Iodine Exposure on Maternal and Fetal Outcomes

Conditions
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Iodine Overload in Pregnancy

Intervention / Treatment
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* Other: dietary iodine restriction on subjects with iodine overload


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Must be pregnant when enrolled in this study. Must have undergone examination of ethiodized-oil HSG before this pregnancy. Clinical diagnosis of iodine excess (with the mean urine iodine concentration ≥250μg/L and the serum iodine concentration >92μg/L). Exclusion Criteria: Having past history of partial or total resection of thyroid glands. Having medical history of thyroid dysfunction before ethiodized-oil HSG examination.

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 45 Years

Sexes Eligible for Study
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Female

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Pregnant women with pre-gestational HSG history<br>All enrolled pregnant women with pre-gestational ethiodized-oil HSG will be followed up without grouping and be kept track for maternal and offspring's health outcomes in this case registry study. | Other: dietary iodine restriction on subjects with iodine overload<br>* In this case registry study (observational study),all intervention will be performed not for research purposes, but only part of routine treatment, which will be recorded in database of the registry study.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| comprehensive pregnant outcomes_prevalence of gestational diabetes | prevalence of gestational diabetes | during the whole pregnancy, from date of verification of pregnancy until the date of termination of pregnancy, assessed up to 10 months | 
| comprehensive pregnant outcomes_prevalence of gestational hypertension | prevalence of gestational hypertension | during the whole pregnancy, from date of verification of pregnancy until the date of termination of pregnancy, assessed up to 10 months | 
| comprehensive pregnant outcomes_prevalence of abnormal pregnancy | prevalence of abnormal pregnancy (stillbirth, abortion, premature delivery) | during the whole pregnancy, from date of verification of pregnancy until the date of termination of pregnancy, assessed up to 10 months | 
| comprehensive pregnant outcomes_rate of cesarean section | rate of cesarean section | at the time of delivery | 
| comprehensive neonatal outcomes at delivery | Apgar scores of neonates | at the time of delivery | 
| comprehensive neonatal outcomes_neonatal weight | birth weight of neonates | at the time of delivery | 
| comprehensive neonatal outcomes_neonatal head circumference | head circumference of neonates | at the time of delivery | 
| comprehensive neonatal outcomes_neonatal height | height of neonates | at the time of delivery | 
| comprehensive neonatal outcomes_neonatal BMI | BMI of neonates | at the time of delivery | 
| comprehensive neonatal outcomes_prevalence of macrosomia or underweight | prevalence of macrosomia or underweight | at the time of delivery | 
| offspring outcomes_prevalence of thyroid dysfunction | prevalence of thyroid dysfunction (hyperthyroidism or hypothyroidism) | from birth to age of 1 year old, assessed every 6 months | 
| offspring outcomes_neurodevelopment evaluation in long term | Norwegian version of the Ages and Stages Questionnaire (ASQ) scores for evaluation of infant neurodevelopment | from birth to age of 1 year old, assessed every 6 months | 
| comprehensive offspring outcomes in long term - weight evaluation | weight of offsprings | from birth to age of 1 year old, assessed every 3-6 months | 
| comprehensive offspring outcomes in long term - height evaluation | height of offsprings | from birth to age of 1 year old, assessed every 3-6 months | 
| comprehensive offspring outcomes in long term - BMI evaluation | BMI of offsprings | from birth to age of 1 year old, assessed every 3-6 months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| prevalence of thyroid dysfunction in pregnancy | evaluation of maternal TSH, T3, T4, FT3, FT4, TRAb,Tg-Ab, TPO-Ab | during the whole pregnancy, from date of verification of pregnancy until the date of termination of pregnancy, assessed up to 10 months | 
| prevalence of iodine overload in neonates | prevalence of infants with urinary iodine concentration ≥200μg/L | within 1 week after birth of neonates |