COMPARATIVE STUDY OF 75g GLUCOSE CHALLENGE TEST (75g GCT) AS A SINGLE STEP SCREENING AND DIAGNOSTIC TEST FOR GESTATIONAL DIABETES MELLITUS (GDM) WITH ORAL GLUCOSE TOLERANCE TEST

Aim: To evaluate role of 75g Glucose challenge test as single step screening and diagnostic test for GDM.

Objective: To find the diagnostic accuracy of 75g GCT for screening and diagnosis of GDM.

Materials and Methods: In this cross- sectional study, 300 antenatal women were screened between 24-28 weeks for GDM with 75 gm GCT. 75g glucose solution was administered orally. Venous plasma glucose level was assessed after 2 hours. Value ≥ 140mg/dl was considered as positive test and <140mg/dl as negative test. 100 gm oral glucose tolerance test (OGTT) was performed within 3-7 days. GDM was diagnosed by Carpenter Coustan criteria. The diagnostic accuracy of 75g GCT was calculated with 100g OGTT as gold standard test.

Results: Incidence of GDM was 2% by 100g OGTT. The sensitivity of single step 75 gm GCT for diagnosing GDM was 100% & specificity was 98.6%.

Conclusion: 75 gm glucose challenge test is a single step test with high sensitivity and specificity for diagnosing GDM.