Peri-conception Key Nutritional Factors and Congenital Heart Disease

Study Overview
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Brief Summary
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The study is a nested case-control study and the purpose is to describe the status of key nutrients(eg.folic acid and vitamins) supplementation among pregnant women in Shanghai, to find out the association between the level of serum key nutrients during peri-conceptional period and the incidence of congenital heart defects (CHD) in newborn, and to provide better preconception care.

Detailed Description
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Congenital heart defects (CHD) are among the most common major congenital anomalies with an incidence of about 8-12/1,000 live births worldwide. The mechanism of CHD is still unclear. Many studies indicated that the level of key nutrients (eg.folic acid and vitamins) during peri-conceptional period might affect the incidence of CHD, but the evidence is limited. The study aimed to explore the association between serum key nutrients during peri-conceptional period and the incidence of CHD in newborn. All couples attending pre-pregnancy physical examination from 11 districts (Minhang District, Huangpu District, Xuhui District, Changning District, Jingan District, Putuo District, Yangpu District, Jiading District, Pudong District，Songjiang District, Qingpu District) in Shanghai from March 2016, are recruited and their blood samples and questionnaires about the supplementation of key nutrients are collected. During the gestation, venous blood of pregnant women at all of three trimesters is taken. Besides, questionnaires about the supplementation of key nutrients at the first antenatal visit are also obtained. The level of serum folic acid, vitamin A and vitamin B12 at preconception and during gestation are measured. Finally, investigators identifies those whose newborns developed CHD during follow-up as the cases. Then, investigators selects four controls for each case from the rest of the cohort by matching on constitutional determinants of CHD such as age and sex. Participants are identified by national identification number during the follow up. The level of serum key nutrients is compared in cases and controls. Univariate and multivariate association analyses will be performed to identify risk factors to CHD by using multivariate logistic regression model.

Official Title
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Peri-conception Key Nutritional Factors and Primary Prevention of Congenital Heart Disease(CHD)

Conditions
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Congenital Heart Disease

Intervention / Treatment
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* Other: observation


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: attend pre-pregnancy physical examination from 11 districts in Shanghai, OR pregnant women present at first antenatal care < 14 week of gestation plan to deliver in Shanghai Exclusion Criteria: none
Sexes Eligible for Study
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All

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 |
| --- | --- |
| CHD birth cohort<br>Cases are identified as those whose newborns screened and confirmed with CHD during the follow-up and four age- and delivery-hospital matched controls are selected for each case from the rest of the cohort. | Other: observation<br>* This is an observational study<br>* Other names: This is an observational study;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| preconceptional maternal serum folate level | a serum sample collected at preconception and/or early conception will be used for examination | usually 6 months before pregnancy | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| early conceptional maternal serum folate deficiency | a serum sample collected at early conception will be used for examination | first antenatal visit (usually 12th-16th gestational week) | 
| The status of serum Vitamin D level | a serum sample collected at preconception and/or first antenatal visit will be used for examination | periconception period ( defined as around 6 months before and the first 3 months of gestation | 
| Pre-conceptional maternal diet folic acid supplement intake | a questionnaire administered at preconception and early conception will be used for estimation based on the dose and frequency of supplements intake | preconception examination (usually 0-6 months before pregnancy) | 
| Peri-conceptional maternal plasma homocysteine level | a plasma sample collected at preconception and first antenatal visit will be used for examination | peri-conception examination ( defined as about 6 months before and 3 months after conception | 
| neonatal congenital heart disease(CHD) status | The newborn babies with heart murmurs(≥ 2 grade) and subnormal Pulse Oximetry reading positive will be considered positive-screened and echocardiography will performed. | Congenital heart disease screening during 6-72 hours after delivery | 
| Peri-conceptional paternal serum folate level | a serum sample collected at preconception and/or early conception will be used for examination | usually between 0-6 months before and 3 months after conception) | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Congenital Heart Disease, Key Nutritional Factors, conception, pregnant