title: Episodic hyperglycaemia in pregnant women with well-controlled Type 1 diabetes mellitus: a major potential factor underlying macrosomia.
abstract: OBJECTIVE
  To test the common assumption that pregnant women who are sufficiently motivated to achieve very good HbA1c levels will record home blood glucose data accurately.
  
  
  METHODS
  A new device was used to download information from electronic blood glucose meters to assess the extent of selectivity in patient glucose diary-keeping.
  
  
  RESULTS
  In an index case, a woman with excellent ambient HbA1c (5.9%; upper limit of normal 6.1%) was observed to have 68% of preprandial blood glucose readings above the target range of 3.5-6.5 mmol/l and a mean (+/- SD) level of 8.9+/-3.9 mmol/l in the corresponding period. No such impression was conveyed by the home monitoring diary. Six pregnant women with well controlled Type 1 diabetes (mean HbA1c 6.6+/-0.2%) exhibited between 42 and 68% of preprandial readings above the target range.
  
  
  CONCLUSIONS
  The frequency of hyperglycaemia has hitherto been underestimated in well controlled pregnant women whose near-perfect home monitoring record is apparently corroborated by near-normal HbA1c levels. These observations provide a hypothesis for understanding of the disappointing continuance of macrosomia despite excellent HbA1c levels throughout pregnancy.
authors.affiliation: Diabetes Unit, Royal Victoria Infirmary, Newcastle upon Tyne, UK.
authors.forename: D
authors.initials: D
authors.lastname: Kyne-Grzebalski
authors.forename: L
authors.initials: L
authors.lastname: Wood
authors.forename: S M
authors.initials: SM
authors.lastname: Marshall
authors.forename: R
authors.initials: R
authors.lastname: Taylor
mesh_terms: D000328:Adult; D015415:Biomarkers / Q000097:blood; D001724:Birth Weight; D001786:Blood Glucose / Q000378:metabolism*; D015190:Blood Glucose Self-Monitoring; D002940:Circadian Rhythm / Q000502:physiology*; D003922:Diabetes Mellitus, Type 1 / Q000097:blood*; D005260:Female; D005320:Fetal Macrosomia / Q000453:epidemiology*; D006442:Glycated Hemoglobin / Q000032:analysis*; D006801:Humans; D006943:Hyperglycemia / Q000150:complications*; D007231:Infant, Newborn; D011247:Pregnancy; D011254:Pregnancy in Diabetics / Q000097:blood*; D012307:Risk Factors
chemical_list: D015415:Biomarkers; D001786:Blood Glucose; D006442:Glycated Hemoglobin