title: Atlantic DIP: high prevalence of abnormal glucose tolerance post partum is reduced by breast-feeding in women with prior gestational diabetes mellitus.
abstract: OBJECTIVE
  Gestational diabetes (GDM) is associated with adverse fetal and maternal outcomes, and identifies women at risk of future type 2 diabetes mellitus (T2DM). Breast-feeding may improve post partum maternal glucose tolerance. Our objective was to identify the prevalence of post partum dysglycemia after GDM, to delineate associated factors and to examine the effect of lactation on post partum glucose tolerance.
  
  
  METHODS
  We compared post partum 75 g oral glucose tolerance test (OGTT) results from 300 women with GDM and 220 controls with normal gestational glucose tolerance (NGT) in five regional centers. Breast-feeding data was collected at time of OGTT. Methods Post partum OGTT results were classified as normal (fasting plasma glucose (FPG) <5.6 mmol/l, 2 h <7.8 mmol/l) and abnormal (impaired fasting glucose (IFG), FPG 5.6-6.9 mmol/l; impaired glucose tolerance (IGT), 2 h glucose 7.8-11 mmol/l; IFG+IGT; T2DM, FPG ≥7 mmol/l±2 h glucose ≥11.1 mmol/l). Binary logistic regression was used to identify factors predictive of persistent hyperglycemia.
  
  
  RESULTS
  Five hundred and twenty women were tested; six (2.7%) with NGT in pregnancy had post partum dysglycemia compared with 57 (19%) with GDM in index pregnancy (P<0.001). Non-European ethnicity (odds ratio (OR) 3.40; 95% confidence interval (CI) 1.45-8.02, P=0.005), family history of T2DM (OR 2.14; 95% CI 1.06-4.32, P=0.034), and gestational insulin use (OR 2.62; 95% CI 1.17-5.87, P=0.019) were associated with persistent dysglycemia. The prevalence of persistent hyperglycemia was significantly lower in women who breast-fed vs bottle-fed post partum (8.2 vs 18.4%, P<0.001).
  
  
  CONCLUSIONS
  Non-European ethnicity, gestational insulin use, family history of T2DM, and elevated body mass index were associated with persistent dysglycemia after GDM. Breast-feeding may confer beneficial metabolic effects after GDM and should be encouraged.
authors.affiliation: Atlantic DIP Investigators, Department of Endocrinology and Diabetes Mellitus, University College Hospital/National University of Ireland, Galway, Republic of Ireland. micilino@hotmail.com
authors.forename: Michael W
authors.initials: MW
authors.lastname: O'Reilly
authors.forename: Gloria
authors.initials: G
authors.lastname: Avalos
authors.forename: Michael C
authors.initials: MC
authors.lastname: Dennedy
authors.forename: Eoin P
authors.initials: EP
authors.lastname: O'Sullivan
authors.forename: Fidelma
authors.initials: F
authors.lastname: Dunne
mesh_terms: D000293:Adolescent; D000328:Adult; D001267:Atlantic Ocean / Q000453:epidemiology; D001786:Blood Glucose / Q000378:metabolism; D001903:Bottle Feeding / Q000639:trends; D001942:Breast Feeding / Q000379:methods / Q000639:trends; D003924:Diabetes Mellitus, Type 2 / Q000097:blood* / Q000453:epidemiology; D016640:Diabetes, Gestational / Q000097:blood* / Q000453:epidemiology; D005260:Female; D018149:Glucose Intolerance / Q000097:blood* / Q000453:epidemiology; D006801:Humans; D007494:Ireland / Q000453:epidemiology; D008875:Middle Aged; D049590:Postpartum Period / Q000097:blood*; D011247:Pregnancy; D015995:Prevalence; D055815:Young Adult
chemical_list: D001786:Blood Glucose