Intrauterine insemination: a European collaborative report.

This report summarizes the data collected in the European Collaborative Report on intrauterine insemination (IUI) with pretreated sperm. A questionnaire concerning methods and results of IUI was sent to European infertility clinics and evaluable data were obtained from 29 of these clinics. A total of 196 pregnancies was reported from a total of 20 clinics. Pregnancy rates per treatment cycle were on average 7.4% of all male infertility, 10.8% for infertility due to hostile cervical mucus and 12.9% for idiopathic infertility, giving an overall pregnancy rate per treatment cycle of 8.4%. The clinical abortion rate was on average 12.2%. The mean number of years of primary infertility in the patient group of the clinics reporting pregnancies was 4.8 years and the mean number of years of primary infertility in the patient group conceiving was 5.2 years. A total of 127 births was reported with a sex ratio (male/female) of 0.512. One congenital malformation was reported. In many clinics, treatment of male infertility with IVF or IUI gave comparable results per treatment cycle. No single factor in the procedure for performing IUI was identified accounting for the different pregnancy rates obtained in the clinics included in this study.