title: Chlamydia trachomatis immunoglobulin G3 seropositivity is a predictor of reproductive outcomes in infertile women with patent fallopian tubes.
abstract: OBJECTIVE
  To determine if Chlamydia trachomatis (C. trachomatis) seropositivity, as detected by the C. trachomatis elementary body (EB)-based enzyme-linked immunosorbent assay [EB ELISA] predicts pregnancy and pregnancy outcome among infertile women with documented tubal patency.
  
  
  METHODS
  Cohort study.
  
  
  METHODS
  Outpatient clinics.
  
  
  METHODS
  In all, 1,250 infertile women with documented tubal patency enrolled in 1 of 2 randomized controlled trials: Pregnancy in Polycystic Ovary Syndrome II; and the Assessment of Multiple Intrauterine Gestations From Ovarian Stimulation.
  
  
  METHODS
  Sera were analyzed for anti-C. trachomatis immunoglobulin G (IgG)1 and IgG3 antibodies, using a research C. trachomatis EB ELISA. The optical density (OD)405 readings of ≥ 0.35 and ≥ 0.1 were considered positive for IgG1 and IgG3, respectively.
  
  
  METHODS
  Primary outcomes included pregnancy, live birth, and ectopic pregnancy. Log-linear regression was used to determine the relative risk after adjusting for age, race, treatment medication, smoking status, and current alcohol use.
  
  
  RESULTS
  A total of 243 (19%) women were seropositive for anti-C. trachomatis IgG3. They tended to be nonwhite and smokers. Anti-C. trachomatis IgG3 seropositive women were significantly less likely to conceive (risk ratio [RR] 0.65, 95% confidence interval [CI] 0.52-0.83) or to have a live birth (RR 0.59, 95% CI 0.43-0.80); these associations were weakened after adjusting for number of hysterosalpingography-documented patent tubes (RR 0.73, 95% CI 0.56-0.97) and (RR 0.73, 95% CI 0.50-1.04), respectively. Anti-C. trachomatis IgG3 seropositive women who conceived had a ×2.7 risk (95% CI 1.40-5.34) of ectopic pregnancy.
  
  
  CONCLUSIONS
  Even in the presence of tubal patency, anti-C. trachomatis IgG3 seropositivity is associated with a lower likelihood of pregnancy. Anti-C. trachomatis IgG3 seropositive women have as high as 3 times the risk of ectopic pregnancy.
  
  
  BACKGROUND
  PPCOSII: NCT00719186 and AMIGOS: NCT01044862.
authors.affiliation: Department of Obstetrics and Gynecology, University of North Carolina, Chapel Hill, North Carolina. Electronic address: asteiner@med.unc.edu.
authors.forename: Anne Z
authors.initials: AZ
authors.lastname: Steiner
authors.affiliation: Department of Obstetrics and Gynecology, Wayne State University, Detroit, Michigan; Department of Obstetrics and Gynecology, Georgia Regents University, Augusta, Georgia.
authors.forename: Michael P
authors.initials: MP
authors.lastname: Diamond
authors.affiliation: Department of Obstetrics and Gynecology, Penn State University, Hershey, Pennsylvania.
authors.forename: Richard S
authors.initials: RS
authors.lastname: Legro
authors.affiliation: Department of Obstetrics and Gynecology, University of Colorado, Aurora, Colorado.
authors.forename: William D
authors.initials: WD
authors.lastname: Schlaff
authors.affiliation: Department of Obstetrics and Gynecology, University of Pennsylvania, Philadelphia, Pennsylvania.
authors.forename: Kurt T
authors.initials: KT
authors.lastname: Barnhart
authors.affiliation: Department of Obstetrics and Gynecology, University of Vermont, Burlington, Vermont.
authors.forename: Peter R
authors.initials: PR
authors.lastname: Casson
authors.affiliation: Department of Obstetrics and Gynecology, University of Michigan, Ann Arbor, Michigan.
authors.forename: Gregory M
authors.initials: GM
authors.lastname: Christman
authors.affiliation: Department of Obstetrics and Gynecology, University of Colorado, Aurora, Colorado.
authors.forename: Ruben
authors.initials: R
authors.lastname: Alvero
authors.affiliation: Department of Obstetrics and Gynecology, University of Oklahoma, Oklahoma City, Oklahoma.
authors.forename: Karl R
authors.initials: KR
authors.lastname: Hansen
authors.affiliation: Department of Medicine, University of Alabama at Birmingham, Birmingham, Alabama.
authors.forename: William M
authors.initials: WM
authors.lastname: Geisler
authors.affiliation: Department of Biostatistics, Yale University, New Haven, Connecticut.
authors.forename: Tracey
authors.initials: T
authors.lastname: Thomas
authors.affiliation: Department of Obstetrics and Gynecology, University of Colorado, Aurora, Colorado.
authors.forename: Nanette
authors.initials: N
authors.lastname: Santoro
authors.affiliation: Department of Biostatistics, Yale University, New Haven, Connecticut.
authors.forename: Heping
authors.initials: H
authors.lastname: Zhang
authors.affiliation: Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland.
authors.forename: Esther
authors.initials: E
authors.lastname: Eisenberg
mesh_terms: D000293:Adolescent; D000328:Adult; D000907:Antibodies, Bacterial / Q000097:blood*; D015415:Biomarkers / Q000097:blood; D016009:Chi-Square Distribution; D002690:Chlamydia Infections / Q000097:blood / Q000150:complications / Q000175:diagnosis / Q000382:microbiology*; D002692:Chlamydia trachomatis / Q000276:immunology*; D004797:Enzyme-Linked Immunosorbent Assay; D005187:Fallopian Tubes / Q000000981:diagnostic imaging / Q000503:physiopathology*; D005260:Female; D006801:Humans; D007074:Immunoglobulin G / Q000097:blood*; D007247:Infertility, Female / Q000097:blood / Q000175:diagnosis / Q000382:microbiology / Q000503:physiopathology / Q000628:therapy*; D016014:Linear Models; D050498:Live Birth; D015999:Multivariate Analysis; D016017:Odds Ratio; D011237:Predictive Value of Tests; D011247:Pregnancy; D018873:Pregnancy Rate; D011271:Pregnancy, Ectopic / Q000382:microbiology; D027724:Reproductive Techniques, Assisted; D018570:Risk Assessment; D012307:Risk Factors; D012698:Serologic Tests; D016896:Treatment Outcome; D014463:Ultrasonography; D055815:Young Adult
chemical_list: D000907:Antibodies, Bacterial; D015415:Biomarkers; D007074:Immunoglobulin G
keywords: Chlamydia trachomatis; ectopic pregnancy; infertility; pregnancy