title: Glycemic targets in the second and third trimester of pregnancy for women with type 1 diabetes.
abstract: OBJECTIVE
  To assess the relationship between second and third trimester glycemic control and adverse outcomes in pregnant women with type 1 diabetes, as uncertainty exists about optimum glycemic targets.
  
  
  METHODS
  Pregnancy outcomes were assessed prospectively in 725 women with type 1 diabetes from the Diabetes and Pre-eclampsia Intervention Trial. HbA1c (A1C) values at 26 and 34 weeks' gestation were categorized into five groups, the lowest, <6.0% (42 mmol/mol), being the reference. Average pre- and postprandial results from an eight-point capillary glucose profile the previous day were categorized into five groups, the lowest (preprandial <5.0 mmol/L and postprandial <6.0 mmol/L) being the reference.
  
  
  RESULTS
  An A1C of 6.0-6.4% (42-47 mmol/mol) at 26 weeks' gestation was associated with a significantly increased risk of large for gestational age (LGA) (odds ratio 1.7 [95% CI 1.0-3.0]) and an A1C of 6.5-6.9% (48-52 mmol/mol) with a significantly increased risk of preterm delivery (odds ratio 2.5 [95% CI 1.3-4.8]), pre-eclampsia (4.3 [1.7-10.8]), need for a neonatal glucose infusion (2.9 [1.5-5.6]), and a composite adverse outcome (3.2 [1.3-8.0]). These risks increased progressively with increasing A1C. Results were similar at 34 weeks' gestation. Glucose data showed less consistent trends, although the risk of a composite adverse outcome increased with preprandial glucose levels between 6.0 and 6.9 mmol/L at 34 weeks (3.3 [1.3-8.0]).
  
  
  CONCLUSIONS
  LGA increased significantly with an A1C ≥6.0 (42 mmol/mol) at 26 and 34 weeks' gestation and with other adverse outcomes with an A1C ≥6.5% (48 mmol/mol). The data suggest that there is clinical utility in regular measurement of A1C during pregnancy.
authors.affiliation: Department of Obstetrics, St. Mary's Hospital, Central Manchester University Hospitals NHS Foundation Trust, Manchester Academic Health Science Centre, Manchester, United Kingdom michael.maresh@cmft.nhs.uk.
authors.forename: Michael J A
authors.initials: MJ
authors.lastname: Maresh
authors.affiliation: Centre for Public Health, School of Medicine, Dentistry and Biomedical Sciences, Queen's University Belfast, Belfast, United Kingdom.
authors.forename: Valerie A
authors.initials: VA
authors.lastname: Holmes
authors.affiliation: Centre for Public Health, School of Medicine, Dentistry and Biomedical Sciences, Queen's University Belfast, Belfast, United Kingdom.
authors.forename: Christopher C
authors.initials: CC
authors.lastname: Patterson
authors.affiliation: Centre for Public Health, School of Medicine, Dentistry and Biomedical Sciences, Queen's University Belfast, Belfast, United Kingdom.
authors.forename: Ian S
authors.initials: IS
authors.lastname: Young
authors.affiliation: Department of Diabetes, Aberdeen Royal Infirmary, Aberdeen, United Kingdom.
authors.forename: Donald W M
authors.initials: DW
authors.lastname: Pearson
authors.affiliation: Department of Diabetes, St. John's Hospital at Howden, West Lothian, United Kingdom.
authors.forename: James D
authors.initials: JD
authors.lastname: Walker
authors.affiliation: Regional Centre for Endocrinology and Diabetes, Royal Victoria Hospital, Belfast, United Kingdom.
authors.forename: David R
authors.initials: DR
authors.lastname: McCance
mesh_terms: D000328:Adult; D001724:Birth Weight; D001786:Blood Glucose / Q000032:analysis*; D015992:Body Mass Index; D003922:Diabetes Mellitus, Type 1 / Q000097:blood* / Q000150:complications; D005260:Female; D006442:Glycated Hemoglobin / Q000378:metabolism; D006801:Humans; D007231:Infant, Newborn; D016015:Logistic Models; D019518:Postprandial Period / Q000502:physiology; D011225:Pre-Eclampsia / Q000097:blood; D011247:Pregnancy; D011248:Pregnancy Complications; D011256:Pregnancy Outcome; D011262:Pregnancy Trimester, Second / Q000097:blood*; D011263:Pregnancy Trimester, Third / Q000097:blood*; D047928:Premature Birth / Q000209:etiology; D011446:Prospective Studies; D016032:Randomized Controlled Trials as Topic; D055815:Young Adult
chemical_list: D001786:Blood Glucose; D006442:Glycated Hemoglobin