THE ESHRE MULTICENTER TRIAL ON THE TREATMENT OF UNEXPLAINED INFERTILITY - A PRELIMINARY-REPORT

Nineteen** European fertility centres participated in a controlled randomized trial aimed at comparing the effectiveness of five methods for the treatment of unexplained infertility. Each centre was invited to employ two of the five treatments being investigated, and the treatment allocated to individual patients was then decided by randomization. The treatments were superovulation alone, and superovulation together with one of the following procedures: intra-uterine insemination (IUI), intra-peritoneal insemination (IPI), gamete intra-Fallopian transfer (GIFT), in-vitro fertilization (IVF). All the patients admitted to the study had experienced > 36 months infertility prior to the start of the trial, and only patients < 38 years of age were included in the investigation. Further, the study was confined to patients with normal Fallopian tubes, and where there was evidence of spontaneous ovulation. Yet another prerequisite for inclusion in the study was that the male partner was 'normal' as regards fertility. Due to unavoidable practical difficulties, the experimental design eventually obtained was severely unbalanced. Nevertheless, objective statistical comparisons were possible among the rive treatments, using non-orthogonal analyses of variance. By the completion of the trial 444 patients had been treated in a total of 649 cycles. There was some statistical evidence that the pregnancy rate obtained from super-ovulation alone was inferior to that obtained by using superovulation together with one of the methods of assisted conception. The pregnancy rate from each method of assisted procreation was found to be vastly better than various estimates of the spontaneous pregnancy rates cited in the literature, and also of the upper limit of the pregnancy rate implied by the pre-treatment period of infertility.