['To compare subsequent pregnancy outcomes after two or more miscarriages in patients with and without congenital uterine anomalies.', 'Case-control study.', 'Nagoya City University Hospital.', 'A total of 42 patients with a bicornuate or septate uterus and 1528 with normal uteri.', 'No surgery.', 'The cumulative success rate for birth, abnormal chromosome karyotype rate in aborted concepti, and the predictive values of the height of the defect/length of the remaining uterine cavity ratio (D/C ratio).', 'Of the total of 1676 patients, 54 (3.2%) had congenital uterine anomalies; 25 (59.5%) of the 42 patients with a bicornuate or septate uterus had a successful first pregnancy after examination, while this was the case for 1096 (71.7%) of the 1528 with normal uteri. There was no difference in the cumulative live-birth rate (78.0% and 85.5%) within the follow-up period. However, the rates for an abnormal chromosome karyotype in aborted concepti in cases with and without uterine anomalies were 15.4% (two of 13) and 57.5% (134 of 233), respectively, with the latter being significantly higher. The D/C ratio in the miscarriage group was also significantly greater than that for the live-birth group.'] Is midline uterine defect size correlated with miscarriage of euploid embryos in recurrent cases?