Effects of Maternal Smoking on Fetal Liver Circulation

Study Overview
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Brief Summary
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According to the hypothesis of this study presented, the effects of smoking on the fetus can be determined by the liver circulation and hepatic metabolism. The basic assumption of this project is; Compensatory and pathological findings can be seen in the fetal liver circulation in babies of mothers who smoke and the findings can be valuable in predicting the direction of fetal development (growth retardation or normal development). In this study, the flow and shunt amounts in the fetal hepatic vessels in normal and smoking pregnant women will be calculated with the help of Doppler US.

Detailed Description
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Smoking is an agent that negatively affects of uteroplacental circulation and fetal development due to the chemical substances it contains, especially carbon monoxide and nicotine. According to the hypothesis of this study presented, the effects of smoking on the fetus can be determined by the liver circulation and hepatic metabolism. The basic assumption of this project is; Compensatory and pathological findings can be seen in the fetal liver circulation in babies of mothers who smoke and the findings can be valuable in predicting the direction of fetal development (growth retardation or normal development). In this study, the flow and shunt amounts in the fetal hepatic vessels in normal and smoking pregnant women will be calculated with the help of Doppler US.Therefore, we try to delineate pathological circulatory pattern in these fetuses and shed light to the mechanism of smoking-induced abnormal fetal development. In addition, the effects of other maternal demographic factors, cigarette amount, cotinine and expiratory carbon monoxide levels (or any correlation between them) on hepatic circulation and fetal development will be examined.

Official Title
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Assessment of Effects of Maternal Smoking on Fetal Liver Circulation With Ultrasonography

Conditions
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Ultrasound, Smoking, Cigarette, Maternal Exposure, Fetal; Circulation, Liver

Intervention / Treatment
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* Other: smoking


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: singleton pregnancy smoking more than one cigarette in a day Exclusion Criteria: fetal anomaly pregnant women with systemic disease younger than 18 years

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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Female

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| otherwise healthy, smoking, singleton pregnant women between 24- 36 weeks<br>Fetal liver circulation will be evaluated with doppler ultrasound, The degree of maternal smoking will be assessed by measuring urine cotinine and exhaled carbon monokside levels | Other: smoking<br>* to assess the effect of smoking of fetal liver circulation with prenatal Doppler Ultrasonography<br>|
| otherwise healthy, non-smoking, singleton pregnant women between 24- 36 weeks<br>Fetal liver circulation will be evaluated with doppler ultrasound, The degree of maternal smoking will be assessed by measuring urine cotinine and exhaled carbon monokside levels | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Comparison of hepatic venous flow between smoking and non- smoking pregnant women | The evaluation of fetal flow parameters will be done with Voluson E6 and Philips EPIQ Elite ultrasound devices. In evaluations, diameters and the time avaraged flow velocities in intraabdominal umbilical vein, left portal vein, main portal vein and ductus venosus (DV) will be measured. The flow volumes will be calculated according to the specified formula and the venous flow of the right and left lobes of the liver and total venous flow of the liver will be determined, adjusted for estimated fetal weight and compared between groups. Flow Formulas; (QUV, QDV, QLPV, QPV): Total venous Hepatic Flow (Qhep)= (QUV-QDV) + QPV Flow to the left liver lobe(QLL)= QUV - (QDV + QleftPV) Flow to the right hepatic lobe (QrightLobe) = QPV + QleftPV | 24-36 weeks of pregnancy | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| The effect of maternal smoking on fetal growth | In the evaluation of fetal growth, fetal biometry (bipariatal diameter, head circumference, abdominal circumference, femur length) will be measured with ultrasound and estimated weight will be calculated with the headlock formula. The calculated weight will be compared with the appropriate (reference) normograms. Cases with estimated fetal weight (EFW) below 10 percentile will be considered as intrauterine growth retardation (IUGR). In both groups (smoking and non-smoking pregnant women) fetal biometry parameters will be measured and estimated fetal weight will be calculated.To be determined if maternal smoking has an effect on fetal growth retardation. | 24-36 weeks of pregnancy | 
| Sensitivity and specificity of maternal expiratory CO levels for detecting maternal smoking during pregnancy |  | 24-36 weeks of pregnancy | 
| Normal references values of fetal umbilical venous and portal venous flow in Turkish Population | Doppler examination of the umbilical vein and portal vein in non-smokig pregnant women will determine the flow rate, flow volume and flow indexes in these vessels. In this way, it is planned to create a reference scale specific to the week of gestation for these parameters in healthy pregnant women in the Turkish population. | 24-36 weeks of pregnancy | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Cotinine, Carbon monoxide, Smoking, Fetal, Liver circulation