Background: The true impact of congenital uterine anomalies on reproductive outcomes is unknown. The aim of this study was to examine differences in the morphology of uterine anomalies found in women with and without a history of recurrent miscarriage.
Methods: A total of 509 women with a history of unexplained recurrent miscarriage and 1976 low risk women were examined for the presence of congenital uterine anomalies by three-dimensional ultrasound. The anomalies were classified according to the American Fertility Society classification. In addition, the size of fundal distortion (F) and the length of the remaining uterine cavity (C) were measured to calculate a distortion ratio (F/F+C). The findings were compared with the measurements obtained in low risk women with an incidental finding of uterine anomaly.
Results: In all, 121 anomalies were detected in the recurrent miscarriage group and 105 in low risk women. There was no significant difference in relative frequency of various anomalies or depth of fundal distortion between the two groups. However, with both arcuate and subseptate uteri, the length of remaining uterine cavity was significantly shorter (P < 0.01) and the distortion ratio was significantly higher (P < 0.01) in the recurrent miscarriage group.
Conclusion: The distortion of uterine anatomy is more severe in congenital anomalies, which are found in women with a history of recurrent first trimester miscarriage.