title: The influence of pregnancy on IDDM complications.
abstract: OBJECTIVE
  Although pregnancy has been associated with an increased progression of certain insulin-dependent diabetes mellitus (IDDM) complications, particularly retinopathy, both the short- and long-term relationships between pregnancy and both neuropathy and macrovascular disease are poorly documented. This study was conducted to comprehensively examine the influence of pregnancy on the development and progression of IDDM complications.
  
  
  METHODS
  Using the Pittsburgh Epidemiology of Diabetes Complications Study population (childhood-onset IDDM), two nested, pair-matched case-control studies were conducted. Women who had completed at least one successful pregnancy (n = 80) were matched to women with no history of pregnancy by age, duration of IDDM, race, and marital history. The first nested study (study 1) compared the prevalences of five IDDM complications between case and control groups. The second nested study (study 2) compared the incidences of the same five complications over an approximate 2-year interval during which the case subjects (n = 30) completed a successful pregnancy.
  
  
  RESULTS
  There were no significant differences in the prevalence rates of coronary heart disease, neuropathy, proliferative retinopathy, lower extremity arterial disease, and overt nephropathy by case-control status, while parity did not predict any complication in multiple logistic analysis (study 1). In study 2, there were small but nonsignificant differences in incidence rates of overt nephropathy and lower extremity arterial disease between the groups, whereas case subjects had almost 3 times the incidence rate of proliferative retinopathy (P = 0.58) and 10 times the incidence rate of neuropathy (P < 0.001) as did other matched control subjects. In multivariate analysis, parity predicted neuropathy incidence but did not predict the incidence of any other complication, including proliferative retinopathy.
  
  
  CONCLUSIONS
  Women with IDDM who experience a pregnancy may not be at an increased risk of diabetes complications later in life. However, in the short term, pregnancy may accelerate the development of some complications, such as neuropathy.
authors.affiliation: Graduate School of Public Health, University of Pittsburgh, Pennsylvania, USA.
authors.forename: A
authors.initials: A
authors.lastname: Hemachandra
authors.forename: D
authors.initials: D
authors.lastname: Ellis
authors.forename: C E
authors.initials: CE
authors.lastname: Lloyd
authors.forename: T J
authors.initials: TJ
authors.lastname: Orchard
mesh_terms: D000328:Adult; D016022:Case-Control Studies; D003327:Coronary Disease / Q000453:epidemiology / Q000503:physiopathology; D003922:Diabetes Mellitus, Type 1 / Q000097:blood / Q000503:physiopathology*; D003925:Diabetic Angiopathies / Q000453:epidemiology / Q000503:physiopathology*; D003929:Diabetic Neuropathies / Q000453:epidemiology / Q000503:physiopathology*; D003930:Diabetic Retinopathy / Q000453:epidemiology / Q000503:physiopathology*; D005260:Female; D006442:Glycated Hemoglobin / Q000032:analysis; D006801:Humans; D015994:Incidence; D009203:Myocardial Infarction / Q000453:epidemiology / Q000503:physiopathology; D011237:Predictive Value of Tests; D011247:Pregnancy; D011254:Pregnancy in Diabetics / Q000097:blood / Q000503:physiopathology*; D015995:Prevalence; D012044:Regression Analysis
chemical_list: D006442:Glycated Hemoglobin