title: Association between cocaine abuse in pregnancy and placenta-associated syndromes using propensity score matching approach.
abstract: OBJECTIVE
  We used propensity scores matching techniques to assess the association between maternal cocaine abuse in pregnancy and the occurrence of placenta-associated syndromes (PAS).
  
  
  METHODS
  Mothers who abused cocaine (n=5026) were matched to controls (n=5026) from a sample of 1,693,197, unexposed mothers in Florida from 1998 to 2007. Cocaine abuse was identified using the ICD-9 principal and secondary diagnosis codes (304.2 for cocaine dependence and 305.6 for cocaine abuse). The outcome of interest, PAS, was identified as any indication in diagnosis field of ICD-9-CM codes for: placental abruption (641.2), oligohydramnios (658.0), placental infarction (656.7, 656.8, 656.9), gestational hypertension (642.3, 642.9), preeclampsia (642.4, 642.5, and 642.7) or eclampsia (642.6).
  
  
  RESULTS
  Nearly 6% of mothers in the study sample experienced a condition associated with PAS prior to matching. Women who abused cocaine were 58% more likely to have PAS when compared to women who did not (OR=1.48, 95% confidence interval: 1.33, 1.66). Women who abused cocaine were at elevated odds for placental abruption, placenta infarction and preeclampsia with the most pronounced odds noted for placental abruption (OR=2.79, 95% confidence interval: 2.19, 3.55).
  
  
  CONCLUSIONS
  These findings indicate that cocaine abuse during pregnancy is associated with more placenta-related disorders than previously reported.
authors.affiliation: Department of Epidemiology and Biostatistics, University of South Florida, Tampa, FL 33612, United States.
authors.forename: Alfred K
authors.initials: AK
authors.lastname: Mbah
authors.forename: Amina P
authors.initials: AP
authors.lastname: Alio
authors.forename: Doris W
authors.initials: DW
authors.lastname: Fombo
authors.forename: Karen
authors.initials: K
authors.lastname: Bruder
authors.forename: Getachew
authors.initials: G
authors.lastname: Dagne
authors.forename: Hamisu M
authors.initials: HM
authors.lastname: Salihu
mesh_terms: D000328:Adult; D019970:Cocaine-Related Disorders / Q000150:complications* / Q000175:diagnosis / Q000453:epidemiology; D015897:Comorbidity; D005260:Female; D005431:Florida / Q000453:epidemiology; D006801:Humans; D008423:Maternal Age; D010922:Placenta Diseases / Q000175:diagnosis / Q000453:epidemiology / Q000209:etiology*; D011247:Pregnancy; D011248:Pregnancy Complications / Q000175:diagnosis / Q000453:epidemiology; D011297:Prenatal Exposure Delayed Effects; D057216:Propensity Score