Association Between Low Plasma Glucose After Oral Glucose Tolerance Test in Pregnancy With Impaired Fetal Growth

Study Overview
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Brief Summary
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Objective: To study the association of low maternal plasma glucose in 2 hour 75 g oral glucose tolerance test (OGTT) in women with impaired birth weight and determinate if this result is predictive of low birth weight (<10th percentile according to the INTERGROWTH-21st newborn weight standards for gestational age/sex). Materials and methods: OGTT at 24-34 week gestation will be performed in pregnant women, the birth weight will be compared between women with low fasting plasma glucose (FPG) (<10th percentile, <65 mg/dL) and normal FPG (≥10th percentile, ≥ 65 mg/dL) also for 1 and 2-hour plasma glucose (1-h PG/2-h PG). Receiver operating characteristic curve analysis will be used to determine the optimal lower OGTT threshold for the prediction of low birth weight.

Detailed Description
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Maternal hypoglycemia has been reported to be linked with low birth weight and poor neonatal outcome. OGTT is performed routinely in pregnancy and hypoglycemia following this screening test is often encountered and the implication of this finding for the fetal growth is unclear. The aim of study will be determinate the association of low maternal plasma glucose in OGTT in women with impaired birth weight and determinate if this result is predictive of low birth weight (<10th percentile according to the INTERGROWTH-21st newborn weight standards for gestational age/sex). The study population will consist of patients with singleton pregnancies who will undergo OGTT at 24-34 weeks, have regular medical checkups throughout their entire pregnancy, deliver on or after 25 week gestation and fulfill inclusion criteria. The birth weight will be compared between women with low fasting plasma glucose (FPG) (<10th percentile, <65 mg/dL*) and normal FPG (≥10th percentile, ≥ 65 mg/dL) also for 1 and 2-hour plasma glucose (1-h PG/2-h PG). Receiver operating characteristic curve analysis will be used to determine the optimal lower OGTT threshold for the prediction of low birth weight. This study will be performed according to the standards of the Helsinki Declaration and approval was obtained from the ethics and educational issues coordinating committee of our University Hospital. *Determinated previously in a pilot study

Official Title
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Association Between Low Plasma Glucose After Oral Glucose Tolerance Test in Pregnancy With Impaired Fetal Growth

Conditions
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Oral Glucose Tolerance Test, Low Birth Weight

Intervention / Treatment
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* Diagnostic Test: 2 hour 75 g Oral glucose tolerance test


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Women with singleton pregnancy who underwent OGTT at 24-34 weeks and had regular medical checkups throughout their entire pregnancy. Gestational age was determined based on the last menstrual period. If gestational age according to the last menstrual period differed by more than 7 days from that according to ultrasonography at <11 weeks, the latter was used to assign gestational age. Exclusion Criteria: Inaccurate gestational age OGTT being drawn outside the prescribed window of 24 to 34 weeks gestation. Patients who could not swallow the OGTT solution or vomited afterward were excluded from the study. Patients who were diagnosed with gestational diabetes at any time during their pregnancy were excluded. The following comorbidities or complications that could affect fetal growth also were excluded: cardiac disease, preeclampsia, gestational hypertension, tobacco use, alcohol intake, stimulant drugs use, maternal systemic diseases (e.g., hypertension, pregestational diabetes, autoimmune disease, thrombotic disease, thyroid disease), intrauterine infectious diseases (e.g., cytomegalovirus, rubella, toxoplasmosis, syphilis), major neonatal anomalies or genetic and structural disorders (e.g., trisomy 21, trisomy 18, trisomy 13, congenital heart disease), placental disorders, and umbilical cord abnormalities. Patients with high risk for preeclampsia, intrauterine growth restriction, trisomy 21, trisomy 18 and trisomy 13 in the first trimester screening test. Patients with incomplete or missing data were also excluded.
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 |
| --- | --- |
| Low plasma glucose<br>This group will be formed by women with low plasma glucose: fasting plasma glucose (<10th percentile, <65 mg/dL), 1 or 2-hour low plasma glucose results after OGTT. | Diagnostic Test: 2 hour 75 g Oral glucose tolerance test<br>* In pregnant women between 24 and 34 weeks of gestational age, plasma glucose was recorded after an overnight fast. Following consumption of 75 g glucose in 200 mL water over 10 min, the equivalent 1 hour and 2 hour values was recorded<br>|
| Normal plasma glucose<br>This group will be formed by women with normal plasma glucose: fasting plasma glucose ( ≥10th percentile, ≥65 mg/dL but < 92 mg/dL), 1 or 2-hour normal glucose (< 180 mg/dL and 153 mg/dL, respectively) results after OGTT. | Diagnostic Test: 2 hour 75 g Oral glucose tolerance test<br>* In pregnant women between 24 and 34 weeks of gestational age, plasma glucose was recorded after an overnight fast. Following consumption of 75 g glucose in 200 mL water over 10 min, the equivalent 1 hour and 2 hour values was recorded<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Birth weight <10th percentile | Birth weight <10th percentile according to the INTERGROWTH-21st newborn weight standards for gestational age/sex. | Newborn birth weight delivered on or after 25 week gestation will be recorded within the first hour after delivery | 
| Birthweight <3th percentile | Birthweight <3th percentile according to the INTERGROWTH-21st newborn weight standards for gestational age/sex. | Newborn birth weight delivered on or after 25 week gestation will be recorded within the first hour after delivery | 
| Birth weight <2500 g | Birth weight <2500 g of newborn delivered on or after 37 week gestation | Newborn birth weight delivered on or after 37 week gestation will be recorded within the first hour after delivery | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Glucose Tolerance Test, Low Birth Weight