No clinical relevance of the height of fundal indentation in subseptate or arcuate uterus: a prospective study

Abstract

The American Fertility Society has classified the arcuate uterus as a minor malformation with a benign clinical behaviour. The aim of this prospective study was to verify whether there is any scientific basis for this differentiation. Patients with at least one early miscarriage and a subseptate or arcuate uterus were admitted for hysteroscopic metroplasty. Patients were allocated to a subseptate uterus group, with an indentation of 1.5cm or more, or an arcuate uterus group, with a smaller indentation. The miscarriage rates after metroplasty were similar between the two groups (14.0% in the subseptate uterus group versus 11.1% in the arcuate uterus group). Before metroplasty, the miscarriage rates were significantly higher in subseptate uterus group, as well as in the arcuate uterus group (both P<0.001). According to these results, there is no evidence to support that the arcuate uterus has a different effect on the reproductive outcome in comparison to the subseptate uterus, neither before nor after surgical correction of the anomaly. Since there is no scientific basis for a separate classification of the arcuate uterus, a review of the classifications of uterine congenital anomalies should be considered as necessary.Congenital uterine malformations have been classified by the American Fertility Society (AFS) since 1988. Although the AFS classification received wide acceptance and is still the most broadly used system, it is associated with various limitations in effective categorization of the anomalies. It is interesting that, until now, none of the other available options have been able to effectively replace the AFS system. Numerous papers indicate septate or subseptate (partial septate) uterus (AFS class V) is a possible cause of an unfavourable pregnancy outcome. Arcuate uterus (AFS class VI), a slight malformation similar to septate uterus, should differ from septate or subseptate uterus, because this ‘minor’ malformation should behave benignly with respect to the septate uterus. The aim of this study was to scientifically validate the difference between the arcuate and subseptate uterus in their effect on reproductive outcome through the results of a metroplasty in both groups of patients. A group of 96 patients, who underwent metroplasty after at least one early miscarriage, was divided into two groups according to the severity of the congenital uterine malformation. Our results indicate that there are no differences in pregnancy outcome after metroplasty either in patients with septate or arcuate utera. The poor pregnancy outcome in women with septate uterus seems not to be correlated to the dimension of the septum itself. There are no scientific bases for a separate classification of the arcuate uterus and it is proposed that a review of the classification of uterine congenital anomalies is necessary.