The placebo response of subfertile couples to attending a tertiary referral centre.
 The objective of this study was to determine whether there was a placebo response to clinic attendance in couples with prolonged (greater than 4 years) subfertility.
 From 4 to 18 years of subfertility we observed a treatment independent cumulative conception rate of 22%, which was independent of the length of subfertility.
 Twenty-seven women conceived after 1 to 4 years' subfertility, and 30 conceived after greater than 4 years' subfertility.
 The fecundity of the latter group was significantly greater than that of women with 1 to 4 years' subfertility, being similar to "normal" subjects who had stopped contraception.
 This study demonstrates that a subgroup of apparently normal women with greater than 4 years' subfertility responded positively to clinic attendance independent of any investigation(s) or therapy.
