Hospital and clinic charts for 100 patients with diagnosed Müllerian anomalies were reviewed. Reproductive history, type of therapy, and treatment results for those patients and for another 44 with a history of exposure to diethylstilbestrol and abnormal hysterosalpingographic findings were recorded and evaluated. The anomaly most frequently associated with reproductive failure was the septate uterus. A new classification, based on degree of failure of normal development, was used in separating the anomalies into groups with similar clinical manifestations, treatment, and prognosis for fetal salvage.