title: Exposure to trimethoprim/sulfamethoxazole but not other FDA category C and D anti-infectives is associated with increased risks of preterm birth and low birth weight.
abstract: OBJECTIVE
  To examine the association between trimethoprim/sulfamethoxazole, other US Food and Drug Administration (FDA) C and D anti-infectives, and non anti-infective FDA C, D, and X drugs used during pregnancy with preterm birth and low birth weight.
  
  
  METHODS
  We carried out a retrospective cohort study based on a 50% random sample of women who gave birth in the Canadian province of Saskatchewan from 1997 to 2000. The association between trimethoprim/sulfamethoxazole, other FDA C and D anti-infectives (fluconazole, clarithromycin, doxycycline, and tetracycline), and non anti-infective FDA C, D, and X drugs used during pregnancy with preterm birth and low birth weight was evaluated using multiple logistic regression, with adjusted odds ratios (aORs) and 95% confidence intervals (CIs) as association measures.
  
  
  RESULTS
  A total of 17 939 women were included in the final analysis. Trimethoprim/sulfamethoxazole was associated with significantly increased risks for preterm birth (aOR 1.51, 95% CI 1.10, 2.08) and low birth weight (aOR 1.67, 95% CI 1.14, 2.46). Exposure to non anti-infective FDA category C, D and X drugs was also associated with increased risks for preterm birth (aOR 1.17, 95% CI 1.09, 1.31) and low birth weight (aOR 1.14, 95% CI 0.92, 1.42), but to a lesser degree. Other FDA C and D anti-infectives were not (statistically) significantly associated with increased risks for preterm birth (aOR 0.93, 95% CI 0.49, 1.77) or low birth weight (aOR 0.65, 95% CI 0.27, 1.60).
  
  
  CONCLUSIONS
  Among FDA C, D and X drugs, trimethoprim/sulfamethoxazole, a folic acid antagonist, has the strongest association with preterm birth and low birth weight.
authors.affiliation: Department of Preventive Medicine, Changzhi Medical College, Changzhi, China.
authors.forename: Jianzhou
authors.initials: J
authors.lastname: Yang
authors.forename: Ri-Hua
authors.initials: RH
authors.lastname: Xie
authors.forename: Daniel
authors.initials: D
authors.lastname: Krewski
authors.forename: Yong-Jin
authors.initials: YJ
authors.lastname: Wang
authors.forename: Mark
authors.initials: M
authors.lastname: Walker
authors.forename: Shi Wu
authors.initials: SW
authors.lastname: Wen
mesh_terms: D000328:Adult; D000367:Age Factors; D000890:Anti-Infective Agents / Q000009:adverse effects* / Q000627:therapeutic use; D002908:Chronic Disease; D015331:Cohort Studies; D016001:Confidence Intervals; D016208:Databases, Factual; D011307:Drug Prescriptions / Q000706:statistics & numerical data; D005260:Female; D006801:Humans; D007230:Infant, Low Birth Weight; D007231:Infant, Newborn; D007234:Infant, Premature; D016015:Logistic Models; D010298:Parity; D011247:Pregnancy; D011251:Pregnancy Complications, Infectious / Q000188:drug therapy*; D047928:Premature Birth / Q000139:chemically induced / Q000453:epidemiology*; D012189:Retrospective Studies; D012307:Risk Factors; D012525:Saskatchewan / Q000453:epidemiology; D012959:Socioeconomic Factors; D015662:Trimethoprim, Sulfamethoxazole Drug Combination / Q000009:adverse effects* / Q000627:therapeutic use; D014481:United States; D014486:United States Food and Drug Administration; D055815:Young Adult
chemical_list: D000890:Anti-Infective Agents; D015662:Trimethoprim, Sulfamethoxazole Drug Combination