A letter to the editor of the journal, Contraception, concerns an article previously published in that journal entitled "WHO study of the Progesterone IUD," and indicts that article as having ignored standards for scientific reporting of prospective trials of contraceptives. The authors of the complaining letter have attempted to reach the authors of the progsterone IUD paper, but have received no response to their questions; in this article, only a corrigendum from WHO disavowing any knowledge or authorization of the disputed paper constitutes the reply. Objections to the IUD study, which had been published in volume 19, number 6, June 1979, p. 575-589, include discrepancies with study dates, incompleteness of data, improper statistical conclusions of significance, errors in menstruation data, problems with computation of medians, and improper conclusions from existing data. The complainants conclude, "it appears that the contradictions and inaccuracies in the report, as well as the substantial incompleteness of the data being reported, prevent this report from being a scientific document of the material under study."