title: Immunoglobulin G antisperm antibodies and prediction of spontaneous pregnancy.
abstract: OBJECTIVE
  To investigate the predictive capacity of immunoglobulin G ASA (direct MAR test) for spontaneous ongoing pregnancy in subfertile couples.
  
  
  METHODS
  Prospective cohort study.
  
  
  METHODS
  Nine fertility centers in The Netherlands.
  
  
  METHODS
  Consecutive ovulatory subfertile couples.
  
  
  METHODS
  A basic fertility workup, including a mixed agglutination reaction test for IgG (MAR test) at first semen analysis.
  
  
  METHODS
  Spontaneous conception resulting in ongoing pregnancy.
  
  
  RESULTS
  We included 1,794 couples, of which 283 (16%) had a spontaneous ongoing pregnancy within 1 year. When a threshold 50% was used for an abnormal test result, the MAR test was positive in 3% of the couples. In the univariable analysis, a positive MAR test >or=50% reduced, albeit not statistically significant, the probability of spontaneous pregnancy (hazard ratio [HR] 0.76, 95% confidence interval [CI] 0.34 to 1.7). In the multivariable analysis, a positive MAR test >or=50% had no contribution in the prediction of spontaneous pregnancy (HR 0.99, 95% CI 0.40 to 2.4).
  
  
  CONCLUSIONS
  This large cohort study shows that the MAR test is not able to predict spontaneous pregnancy chances. Its routine use in the basic fertility workup for identification of couples with low spontaneous pregnancy chances is not justified.
authors.affiliation: Center for Reproductive Medicine, Academic Medical Center, Amsterdam, The Netherlands.
authors.forename: Esther
authors.initials: E
authors.lastname: Leushuis
authors.forename: Jan Willem
authors.initials: JW
authors.lastname: van der Steeg
authors.forename: Pieternel
authors.initials: P
authors.lastname: Steures
authors.forename: Sjoerd
authors.initials: S
authors.lastname: Repping
authors.forename: Willem
authors.initials: W
authors.lastname: Schöls
authors.forename: Fulco
authors.initials: F
authors.lastname: van der Veen
authors.forename: Ben Willem J
authors.initials: BW
authors.lastname: Mol
authors.forename: Peter G A
authors.initials: PG
authors.lastname: Hompes
mesh_terms: D000328:Adult; D000465:Algorithms; D000906:Antibodies / Q000032:analysis / Q000097:blood*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007074:Immunoglobulin G / Q000276:immunology* / Q000378:metabolism; D007247:Infertility, Female / Q000097:blood / Q000175:diagnosis* / Q000209:etiology / Q000276:immunology; D008297:Male; D008875:Middle Aged; D011247:Pregnancy; D049168:Pregnancy, Unplanned / Q000097:blood* / Q000276:immunology / Q000378:metabolism; D011379:Prognosis; D012307:Risk Factors; D013094:Spermatozoa / Q000276:immunology* / Q000378:metabolism
chemical_list: D000906:Antibodies; D007074:Immunoglobulin G