title: Correspondence between first-trimester fasting glycaemia, and oral glucose tolerance test in gestational diabetes diagnosis.
abstract: OBJECTIVE
  To evaluate the correspondence between first-trimester fasting glycaemia and the results of the OGTT in diagnosing gestational diabetes (GDM).
  
  
  METHODS
  The medical records of all consecutive women who had undergone a diagnostic OGTT, performed according to the IADPSG, during the past year were retrospectively reviewed. All first-trimester fasting glucose values greater or equal to 5.1 mmol/L (92 mg/dL), recommended as a diagnostic value, were also verified for each patient in this cohort. Moreover, a ROC curve and a multiple logistic-regression model were constructed to calculate the predictive capability of this cut-off value in diagnosing GDM.
  
  
  RESULTS
  In our population of 738 eligible pregnant women, an 11.9% prevalence of GDM was revealed by OGTT. However, when the first-trimester fasting glucose value for each patient was retrospectively considered, there were a further 29 patients who should have been diagnosed as GDM cases (glycaemia ≥ 5.1 mmol/L), although their OGTT was normal. Yet, when the value of fasting glucose was considered not diagnostic, but only predictive, an AUC of 0.614 (95% CI: 0.544-0.684) and an aOR of 7.1 (95% CI: 3.8-13.1) was obtained in these patients compared with the reference group (fasting glucose < 5.1 mmol/L).
  
  
  CONCLUSIONS
  There was no complete correspondence in diagnosing GDM between the first-trimester fasting glucose value and the results of a 2-h 75-g OGTT performed early in the third trimester. However, albeit not diagnostic, a fasting glucose value greater or equal to 5.1 mmol/L may be considered a highly predictive risk factor for GDM.
authors.affiliation: Department of Obstetrics and Gynecology, University of Messina, via Consolare Valeria 1, 98125 Messina, Italy. fcorrado@unime.it
authors.forename: F
authors.initials: F
authors.lastname: Corrado
authors.forename: R
authors.initials: R
authors.lastname: D'Anna
authors.forename: M L
authors.initials: ML
authors.lastname: Cannata
authors.forename: M L
authors.initials: ML
authors.lastname: Interdonato
authors.forename: B
authors.initials: B
authors.lastname: Pintaudi
authors.forename: A
authors.initials: A
authors.lastname: Di Benedetto
mesh_terms: D000328:Adult; D001786:Blood Glucose / Q000378:metabolism*; D016640:Diabetes, Gestational / Q000097:blood / Q000175:diagnosis* / Q000453:epidemiology; D005215:Fasting / Q000097:blood; D005260:Female; D005951:Glucose Tolerance Test; D006442:Glycated Hemoglobin / Q000378:metabolism*; D006801:Humans; D007558:Italy / Q000453:epidemiology; D016015:Logistic Models; D008403:Mass Screening; D017410:Practice Guidelines as Topic; D011247:Pregnancy; D011261:Pregnancy Trimester, First; D012372:ROC Curve; D012016:Reference Values; D012189:Retrospective Studies
chemical_list: D001786:Blood Glucose; D006442:Glycated Hemoglobin; C517652:hemoglobin A1c protein, human