title: Maternal Antibodies to Chlamydia trachomatis and Risk of Gastroschisis.
abstract: BACKGROUND
  Gastroschisis, a birth defect of the abdominal wall, is increasing in prevalence. The largest increase in prevalence has been observed among young mothers (<20 years). The prevalence of Chlamydia trachomatis (CT) infection is highest among young women and has also been increasing over time. The objective was to investigate the association between immunoglobulin G antibodies to Chlamydia trachomatis (CT) (anti-CT) and Chlamydial heat shock protein 60 (anti-CHP60) during pregnancy, and risk of gastroschisis among offspring.
  
  
  METHODS
  We conducted a nested case-control study of 292 gastroschisis cases identified from the Congenital Malformations Register and 826 live born controls matched on age and birth year within the Finnish Maternity Cohort. Early pregnancy serum samples were used to categorize women by seropositivity to anti-CT and anti-CHP60. Women seronegative for anti-CT and anti-CHP60 served as the reference. We used conditional logistic regression to calculate odds ratios (ORs) and 95% confidence intervals (CIs). Effect measure modification by maternal age (<25 years, ≥25 years) was also assessed.
  
  
  RESULTS
  Seropositivity to anti-CT (17.8% of cases vs. 16.0% of controls) or anti-CHP60 (23.6% of cases vs. 22.0% of controls) was not associated with gastroschisis. Although, the OR for seropositivity to anti-CT alone was slightly elevated (OR, 1.19; 95% CI, 0.73-1.94), specifically among young mothers (<25 years) (OR, 1.65; 95% CI, 0.81-3.37), the results were imprecise.
  
  
  CONCLUSIONS
  Chlamydia infection, as measured by immunoglobulin G antibodies to CT and CHP60, is not associated with gastroschisis, however, our assays were not able to distinguish recent infection.Birth Defects Research 109:543-549, 2017.© 2017 Wiley Periodicals, Inc.
authors.affiliation: Department of Epidemiology, Boston University School of Public Health, Boston, Massachusetts.
authors.forename: Samantha E
authors.initials: SE
authors.lastname: Parker
authors.affiliation: Department of Epidemiology, Boston University School of Public Health, Boston, Massachusetts.
authors.forename: Martha M
authors.initials: MM
authors.lastname: Werler
authors.affiliation: National Institute for Health and Welfare, Information Services Department, Helsinki, Finland.
authors.forename: Mika
authors.initials: M
authors.lastname: Gissler
authors.affiliation: National Institute for Health and Welfare, Information Services Department, Helsinki, Finland.|National Institute for Health and Welfare, Prenatal Serology Laboratory, Oulu, Finland.
authors.forename: Heljä-Marja
authors.initials: HM
authors.lastname: Surcel
mesh_terms: D000328:Adult; D000907:Antibodies, Bacterial / Q000097:blood*; D016022:Case-Control Studies; D002690:Chlamydia Infections / Q000097:blood* / Q000453:epidemiology; D002692:Chlamydia trachomatis / Q000276:immunology*; D015331:Cohort Studies; D005260:Female; D005387:Finland / Q000453:epidemiology; D020139:Gastroschisis / Q000097:blood / Q000453:epidemiology / Q000209:etiology*; D006801:Humans; D007074:Immunoglobulin G / Q000097:blood; D011247:Pregnancy; D011251:Pregnancy Complications, Infectious / Q000097:blood* / Q000276:immunology; D011297:Prenatal Exposure Delayed Effects / Q000097:blood / Q000453:epidemiology / Q000209:etiology; D012307:Risk Factors; D016036:Seroepidemiologic Studies; D055815:Young Adult
chemical_list: D000907:Antibodies, Bacterial; D007074:Immunoglobulin G
keywords: Chlamydia trachomatis; antibodies; gastroschisis; heat shock protein