Three hypotheses have been most often cited on the link between infertility and psychosocial distress: (1) psychosocial problems trigger infertility; (2) infertility triggers psychosocial distress; and (3) there is an interactive causal relationship between infertility and psychosocial distress. The controlled research on these three hypotheses was reviewed. The thirty publications that met inclusion criteria provide convincing evidence that, taken as a whole, patients diagnosed and treated in infertility clinics show significantly higher levels of psychosocial distress than do control groups. As well, in general, female patients score higher on psychosocial distress measures than males. However, the authors conclude that research designs to date have failed to control crucial variables that permit conclusive empirical tests of the three hypotheses. The paper closes with recommendations for future research that would accelerate the evaluation of scientific data available on the subject.