title: Self-reported mechanical problems during condom use and semen exposure. Comparison of two randomized trials in the United States of America and Brazil.
abstract: OBJECTIVE
  To compare self-reported condom use problems and objectively determined semen exposure in 2 populations.
  
  
  METHODS
  Two randomized crossover trials in the United States and Brazil compared the failure rates of the female condom (FC) and male condom (MC). Participants used both condom types, completed condom-specific questionnaires to report problems, and collected precoital and postcoital samples of vaginal fluid. Prostate-specific antigen (PSA) was detected by immunoassay.
  
  
  RESULTS
  Problems with condom use were reported less frequently in the Brazilian study (rate difference: FC = 24%, P <0.0001, MC = 5%, P = 0.003). By contrast, the PSA detection rates were similar for both the FC and the MC (rate difference: FC = 2%, MC = 1%, not significant). These results suggest that the PSA detection rate was similar in the 2 study groups and that self-reported problems may be a less reliable measure of condom failure.
  
  
  CONCLUSIONS
  Use of biomarkers of condom failure like PSA may help to strengthen the validity of studies promoting behavior change for the prevention of sexually transmitted diseases.
authors.affiliation: Division of Reproductive Health, Centers for Disease Control and Prevention, Atlanta, Georgia, USA.
authors.forename: Michael P
authors.initials: MP
authors.lastname: Chen
authors.forename: Maurizio
authors.initials: M
authors.lastname: Macaluso
authors.forename: Richard
authors.initials: R
authors.lastname: Blackwell
authors.forename: Loren
authors.initials: L
authors.lastname: Galvao
authors.forename: Andrzej
authors.initials: A
authors.lastname: Kulczycki
authors.forename: Juan
authors.initials: J
authors.lastname: Diaz
authors.forename: Denise J
authors.initials: DJ
authors.lastname: Jamieson
authors.forename: Ann
authors.initials: A
authors.lastname: Duerr
mesh_terms: D000293:Adolescent; D000328:Adult; D001938:Brazil; D003075:Coitus; D017280:Condoms; D019111:Single-Use Internal Condom; D003267:Contraception / Q000706:statistics & numerical data*; D018592:Cross-Over Studies; D004868:Equipment Failure; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D017430:Prostate-Specific Antigen / Q000032:analysis*; D012661:Semen / Q000737:chemistry; D011795:Surveys and Questionnaires; D014481:United States; D014621:Vagina / Q000737:chemistry
chemical_list: D017430:Prostate-Specific Antigen