Feasibility of surveillance of changes in human fertility and semen quality

To show that male fertility is declining is not simple. Few men volunteer a nd recruitment bias may lead to over-representation of the subfertile. Seme n analysis has errors arising from counting and poorly standardized criteri a, which may be overcome by automation. Time to pregnancy (TTP)-the number of menstrual cycles taken to conceive-measures fertility and allows male re cruitment bias to be estimated. We review automated measurement of sperm co ncentration, motility and morphology and present a preliminary report on a study to assess a retrospective TTP questionnaire, recruitment bias and fea sibility for large-scale surveillance of fertility.