title: Diagnostic value of haemoglobin A1cin post-partum screening of women with gestational diabetes mellitus.
abstract: The aim of this study was to evaluate whether women with gestational diabetes mellitus could be screened using HbA1cfor glucose metabolism status at 6-12 weeks post-partum.
  
  
  
  We enrolled 699 pregnant women diagnosed with gestational diabetes mellitus from October 2005 to December 2013. A 75-g oral glucose tolerance test (OGTT) and HbA1cmeasurement were performed at 6-12 weeks after delivery.
  
  
  
  The prevalence of overt diabetes and pre-diabetes were 5.2% (n = 36) and 49.1% (n = 343), respectively, when using the 75-g OGTT as the gold standard. HbA1calone identified 2.9% (n = 20) as having overt diabetes and 32.2% (n = 225) as having pre-diabetes. When American Diabetes Association cut-offs were applied, the sensitivity and specificity for HbA1cto diagnose overt diabetes were 19.4% and 98.0%, respectively. Pre-diabetes, according to the HbA1ccriterion, had 41.2% sensitivity and 72.2% specificity. The misclassifications identified 97 positive differences, 233 negative differences and 369 ties (P < 0.05). The area under the receiver operating characteristic curves for detecting diabetes and pre-diabetes were 0.615 [95% confidence interval (95% CI), 0.515 to 0.716] and 0.588 (95% CI, 0.545 to 0.630), respectively.
  
  
  
  HbA1cmay not be sensitive enough for an accurate diagnosis, but it is highly specific for diagnosing overt diabetes at 6-12 weeks post-partum in women with previous gestational diabetes mellitus.
authors.affiliation: Department of Internal Medicine, CHA Bundang Medical Center, CHA University, Seongnam, Republic of Korea.
authors.forename: K-S
authors.initials: KS
authors.lastname: Kim
authors.affiliation: Department of Internal Medicine, CHA Bundang Medical Center, CHA University, Seongnam, Republic of Korea.
authors.forename: S-K
authors.initials: SK
authors.lastname: Kim
authors.affiliation: Department of Internal Medicine, CHA Bundang Medical Center, CHA University, Seongnam, Republic of Korea.
authors.forename: Y-W
authors.initials: YW
authors.lastname: Cho
authors.affiliation: Department of Internal Medicine, CHA Bundang Medical Center, CHA University, Seongnam, Republic of Korea.
authors.forename: S W
authors.initials: SW
authors.lastname: Park
mesh_terms: D000328:Adult; D015415:Biomarkers / Q000378:metabolism; D001786:Blood Glucose / Q000378:metabolism; D016640:Diabetes, Gestational / Q000175:diagnosis*; D005260:Female; D005951:Glucose Tolerance Test / Q000379:methods / Q000592:standards; D006442:Glycated Hemoglobin / Q000378:metabolism*; D006801:Humans; D011181:Postnatal Care / Q000379:methods; D011236:Prediabetic State / Q000175:diagnosis; D011247:Pregnancy; D056910:Republic of Korea; D012680:Sensitivity and Specificity
chemical_list: D015415:Biomarkers; D001786:Blood Glucose; D006442:Glycated Hemoglobin