Estimation of the prevalence and incidence of infertility in a population: a pilot study.

A pilot study was undertaken to investigate the use of a mailed questionnaire to estimate the prevalence and incidence of infertility in a population, and the demand for medical advice about infertility. The objectives were to investigate the response rate, the acceptability and comprehensibility of the questionnaire, and to provide initial results. After elimination of undelivered questionnaires, a response rate of 82% was obtained. One question was found to be misleading in its wording: this question can be clarified before the questionnaire is used more widely. The results from analysis of the pilot study indicate that 20% to 35% of couples take more than 1 year to conceive, at some stage in their reproductive history. A much larger study, with a sample of approximately 3,500, is required to provide more accurate information.