title: Stress, distress and outcome of assisted reproductive technology (ART): a meta-analysis.
abstract: BACKGROUND
  A number of studies have investigated the relationship between psychological factors such as stress and distress (measured as anxiety and depression) and outcomes of assisted reproductive technology (ART). The results, however, are inconsistent, and the strength of any associations remains to be clarified. We conducted a systematic review and meta-analysis of the results of studies reporting on the associations between stress, anxiety, and depression and ART outcomes.
  
  
  METHODS
  Prospective studies reporting data on associations between stress or distress in female patients and ART outcome were identified and evaluated by two independent researchers according to an a priori developed codebook. Authors were contacted in cases of insufficient data reporting. Stress was defined as perceived stress, work-related stress, minor life events or major life events, and distress was defined as anxiety or depression.
  
  
  RESULTS
  A total of 31 prospective studies were included. Small, statistically significant, pooled effect sizes were found for stress [ESr, effect size correlation) = -0.08; P = 0.02, 95% confidence interval (CI): -0.15, -0.01], trait anxiety (ESr = -0.14; P = 0.02, 95% CI: -0.25, -0.03) and state anxiety (ESr = -0.10, P = 0.03, 95% CI: -0.19, -0.01), indicating negative associations with clinical pregnancy rates. A non-significant trend (Esr = -0.11, P = 0.06) was found for an association between depression and clinical pregnancy. For serum pregnancy tests and live birth rates, associations between trait anxiety or state anxiety were not significant. The fail safe number did not exceed the suggested criterion in any analyses, between-study heterogeneity was considerable and the mean age, mean duration of infertility and percentage of first time ART attenders in the study samples were found to moderate several of the associations.
  
  
  CONCLUSIONS
  Small but significant associations were found between stress and distress and reduced pregnancy chances with ART. However, there were a limited number of studies and considerable between-study heterogeneity. Taken together, the influence of stress and distress on ART outcome may appear somewhat limited.
authors.affiliation: Department of Psychology, University of Aarhus, Jens Chr Skous vej 4, 8000 Aarhus, Denmark. signese@psy.au.dk
authors.forename: S M S
authors.initials: SM
authors.lastname: Matthiesen
authors.forename: Y
authors.initials: Y
authors.lastname: Frederiksen
authors.forename: H J
authors.initials: HJ
authors.lastname: Ingerslev
authors.forename: R
authors.initials: R
authors.lastname: Zachariae
mesh_terms: D000328:Adult; D001007:Anxiety / Q000150:complications; D003863:Depression / Q000150:complications; D005260:Female; D005307:Fertilization in Vitro / Q000379:methods; D006801:Humans; D007246:Infertility / Q000150:complications* / Q000628:therapy; D011247:Pregnancy; D011248:Pregnancy Complications; D011256:Pregnancy Outcome; D011446:Prospective Studies; D027724:Reproductive Techniques, Assisted; D020554:Sperm Injections, Intracytoplasmic / Q000379:methods; D013315:Stress, Psychological / Q000150:complications*