Early Screening for Gestational Diabetes Mellitus

Study Overview
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Brief Summary
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The working hypothesis of this proposal is that screening for gestational diabetes mellitus as early as the 1st trimester is efficient for detecting the forthcoming presence or absence of gestational diabetes mellitus. The investigators long-term goal is the prevention of gestational diabetes mellitus onset i.e. the prevention of progression to gestational diabetes mellitus, in order to enable delivery of appropriate counselling, diagnostics and treatment for pregnant women, as well as to improve pregnancy outcomes. Therefore, robust 1st trimester screening criteria is needed. The overall objective of this proposal is to determine an accurate and valid 1st trimester 1h post 50g oral glucose challenge test plasma glucose cut-off value that is predictive of gestational diabetes mellitus onset.

Official Title
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Early Screening for Gestational Diabetes Mellitus

Conditions
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Gestational Diabetes Mellitus

Intervention / Treatment
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* Procedure: 50 g oral glucose challenge test - 75 g oral glucose tolerance test


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Age > 18 yrs Gestational age between 6 and 13 weeks from last menstrual period, Alcohol < 2 drinks/day Not involved in regular high intensity physical activity Singleton pregnancy Otherwise good health status. Exclusion Criteria: Type 1 or type 2 diabetes Taking drugs interfering with glucose metabolism

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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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 |
| --- | --- |
| Pregnant women 6-13 weeks<br> | Procedure: 50 g oral glucose challenge test - 75 g oral glucose tolerance test<br>* 50 g oral glucose challenge test at 6-13 weeks of gestation and 75 g oral glucose tolerance test at 24-28 weeks of gestation.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| oral glucose challenge test plasma glucose value | the sensitivity, specificity, positive and negative predictive values of oral glucose challenge test plasma glucose >= 7.8 mmol/L during the 1st trimester (6-13 weeks of gestation), as compared with fasting 75g glucose oral glucose tolerance test performed between the 24th and 28th weeks of gestation (the Canadian Diabetes Association - CDA gold standard). | 6-13 weeks | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| oral glucose challenge test plasma glucose cut-off value | 1st trimester 1h post 50g oral glucose challenge test plasma glucose cut-off value that offers optimal sensibility and specificity compared to the 75g oral glucose tolerance test performed between the 24th and 28th weeks of gestation, based on the ROC curve and the maximal likelihood ratio for a positive test. | 6-13 weeks |