title: Evaluation of the impact of universal testing for gestational diabetes mellitus on maternal and neonatal health outcomes: a retrospective analysis.
abstract: BACKGROUND
  Gestational diabetes (GDM) affects a substantial proportion of women in pregnancy and is associated with increased risk of adverse perinatal and long term outcomes. Treatment seems to improve perinatal outcomes, the relative effectiveness of different strategies for identifying women with GDM however is less clear.This paper describes an evaluation of the impact of a change in policy from selective risk factor based offering, to universal offering of an oral glucose tolerance test (OGTT) to identify women with GDM on maternal and neonatal outcomes.
  
  
  METHODS
  Retrospective six year analysis of 35,674 births at the Women's and Newborn unit, Bradford Royal Infirmary, United Kingdom.
  
  
  RESULTS
  The proportion of the whole obstetric population diagnosed with GDM increased almost fourfold following universal offering of an OGTT compared to selective offering of an OGTT; Rate Ratio (RR) 3.75 (95% CI 3.28 to 4.29), the proportion identified with severe hyperglycaemia doubled following the policy change; 1.96 (1.50 to 2.58). The case detection rate however, for GDM in the whole population and severe hyperglycaemia in those with GDM reduced by 50-60%; 0.40 (0.35 to 0.46) and 0.51 (0.39 to 0.67) respectively. Universally offering an OGTT was associated with an increased induction of labour rate in the whole obstetric population and in women with GDM; 1.43 (1.35 to 1.50) and 1.21 (1.00 to1.49) respectively. Caesarean section, macrosomia and perinatal mortality rates in the whole population were similar. For women with GDM, rate of caesarean section; 0.70 (0.57 to 0.87), macrosomia; 0.22 (0.15 to 0.34) and perinatal mortality 0.12 (0.03 to 0.46) decreased following the policy change.
  
  
  CONCLUSIONS
  Universally offering an OGTT was associated with increased identification of women with GDM and severe hyperglycaemia and with neonatal benefits for those with GDM. There was no evidence of benefit or adverse effects in neonatal outcomes in the whole obstetric population.
authors.affiliation: Bradford Institute for Health Research, Bradford Royal Infirmary, Bradford, UK. diane.farrar@bthft.nhs.uk.
authors.forename: Diane
authors.initials: D
authors.lastname: Farrar
authors.forename: Lesley
authors.initials: L
authors.lastname: Fairley
authors.forename: John
authors.initials: J
authors.lastname: Wright
authors.forename: Derek
authors.initials: D
authors.lastname: Tuffnell
authors.forename: Donald
authors.initials: D
authors.lastname: Whitelaw
authors.forename: Debbie A
authors.initials: DA
authors.lastname: Lawlor
mesh_terms: D002585:Cesarean Section / Q000639:trends; D016640:Diabetes, Gestational / Q000175:diagnosis* / Q000453:epidemiology* / Q000628:therapy; D003955:Diagnostic Tests, Routine; D005260:Female; D005320:Fetal Macrosomia / Q000453:epidemiology; D005951:Glucose Tolerance Test; D006291:Health Policy; D006801:Humans; D006943:Hyperglycemia / Q000175:diagnosis / Q000453:epidemiology; D007231:Infant, Newborn; D007751:Labor, Induced / Q000706:statistics & numerical data; D054238:Perinatal Mortality / Q000639:trends; D011247:Pregnancy; D012189:Retrospective Studies; D006113:United Kingdom / Q000453:epidemiology