title: Linking a pharmaceutical claims database with a birth defects registry to investigate birth defect rates of suspected teratogens.
abstract: OBJECTIVE
  Data linkage of population administrative data is being investigated as a tool for pharmacovigilance in pregnancy in Australia. Records of prescriptions of known or suspected teratogens dispensed to pregnant women have been linked to a birth defects registry to determine if defects associated with medicine exposure can be detected.
  
  
  METHODS
  The Pharmaceutical Benefits Scheme is a national claims database that has been linked with population-based data to extract linkages for women with a pregnancy event in Western Australia from 2002 to 2005 (n = 106 074). Records of births to the women who were dispensed medicines in categories D or X of the Australian ADEC pregnancy risk category were linked to the Birth Defects Registry of Western Australia. Population rates of registered birth defects per 1000 births were calculated for each medicine.
  
  
  RESULTS
  There were 47 medicines dispensed at least once during pregnancy with 23 associated with a registered birth defect to a woman dispensed the medicine. When the birth defect rate for each medicine was compared with the rate for all other women not dispensed that medicine, most medicines showed an increased risk. Medicines with the higher risks were medroxyprogesterone acetate (OR: 1.8; 95%CI: 1.4-2.3), follitropin alfa (OR: 2.5; 95%CI: 1.2-5.0), carbamazepine (OR: 3.1; 95%CI: 1.7-5.6) and enalapril maleate (OR: 8.1; 95%CI: 1.6-41.7).
  
  
  CONCLUSIONS
  Many known associations between medicines and birth defects were identified, suggesting that linked administrative data could be an important means of pharmacovigilance in pregnancy in Australia.
authors.affiliation: Telethon Institute for Child Health Research, Centre for Child Health Research, The University of Western Australia, West Perth, Western Australia, Australia. lync@ichr.uwa.edu.au
authors.forename: Lyn
authors.initials: L
authors.lastname: Colvin
authors.forename: Linda
authors.initials: L
authors.lastname: Slack-Smith
authors.forename: Fiona J
authors.initials: FJ
authors.lastname: Stanley
authors.forename: Carol
authors.initials: C
authors.lastname: Bower
mesh_terms: D000014:Abnormalities, Drug-Induced / Q000453:epidemiology / Q000209:etiology*; D016907:Adverse Drug Reaction Reporting Systems / Q000458:organization & administration*; D016208:Databases, Factual; D064420:Drug-Related Side Effects and Adverse Reactions; D005260:Female; D006801:Humans; D007231:Infant, Newborn; D008297:Male; D008498:Medical Record Linkage / Q000379:methods*; D016347:Medical Records Systems, Computerized / Q000458:organization & administration; D004364:Pharmaceutical Preparations / Q000145:classification; D011247:Pregnancy; D012042:Registries / Q000706:statistics & numerical data*; D014904:Western Australia / Q000453:epidemiology
chemical_list: D004364:Pharmaceutical Preparations