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**Overview**: Glucose Tolerance Test Pregnancy 75g Panel**Introduction**: The Glucose Tolerance Test Pregnancy 75g Panel is a diagnostic tool designed to screen for gestational diabetes using plasma samples. In India, the 75g OGTT (IADPSG criteria) is widely used for GDM diagnosis, affecting ~10-20 percent of pregnancies, with early detection reducing macrosomia and preeclampsia. High morbidity from under-screening in rural/low-SES pregnant women, limited labs, delayed diet/insulin leading to adverse outcomes. Per endocrinology practices aligned with ICMR, DIPSI, and FOGSI guidelines, the test employs spectrophotometry for fasting/1-2 hour glucose over 1-2 days with high accuracy, valuable for universal/high-risk screening. This diagnostic falls under pregnancy screening and targets pregnant women (24-28 weeks or earlier if risk), addressing accurate detection to guide management and improve perinatal health. With elevated morbidity due to under-screening, the test supports public health efforts by enabling precise GDM identification and reducing complications. Its plasma-based approach ensures reliable glucose measurement.**Other Names**: GTT 75g Pnl.**FDA Status**: FDA approved, CLIA certified for biochemistry, compliant with 2025 standards.**Historical Milestone**: 75g IADPSG standard; in India, preferred in many centers.**Purpose**: The test assesses 3 parameters including fasting glucose to guide gestational diabetes screening, detect hyperglycemia, inform therapy.**Test Parameters**: 1. Fasting Glucose, 2. 1-Hour Glucose, 3. 2-Hour Glucose.**Pretest Condition**: Fasting 10-12 hours required; patients should be pregnant.**Specimen**: 3 mL plasma in NaF tube (multiple draws), transported within specified times to maintain sample viability.**Sample Stability at Room Temperature**: 8 hours with proper handling to preserve analyte integrity, ensuring reliable test performance.**Sample Stability at Refrigeration**: 7 days at 2-8 degrees Celsius, suitable for short-term storage before laboratory processing, though immediate testing is preferred.**Sample Stability at Frozen**: 6 months at -20 degrees Celsius, allowing long-term storage for retesting, though freezing may affect some analytes.**Medical History**: Patients should provide details on pregnancy week, risk factors.**Consent**: Written informed consent is required, detailing the test's purpose, potential risks of untreated GDM including complications, benefits of screening, and minimal discomfort from multiple draws.**Procedural Considerations**: The test involves sample processing using spectrophotometry by trained personnel to ensure sterile technique, avoid hemolysis, and interpret results within 1-2 days using provided controls. Laboratories must maintain a controlled environment, adhere to quality assurance protocols.**Factors Affecting Result Accuracy**: Delays beyond stability periods, improper storage conditions, hemolysis, or non-compliance with load can affect results. Correlation with clinical evaluation or additional testing is recommended to confirm findings.**Clinical Significance**: Abnormal values diagnose GDM, necessitating specialist input.**Specialist Consultation**: Obstetricians should be consulted for management.**Additional Supporting Tests**: DIPSI single-point for confirmation.**Test Limitations**: Requires compliance; comprehensive approach required.**References**: Indian Journal of Obstetrics and Gynaecology 2024, GDM Studies India 2023. |
