Relevance of Uterine Subseptations: What Length Should Warrant Hysteroscopic Resection?

Existing recommendations warrant correction of uterine subseptations longer than 10 mm. We assessed whether a different subseptation length is indicated for intervention by evaluating the postoperative decrease in cavity width.

We conducted a prospective controlled cohort study at a university center. Healthy women and women with subseptations were evaluated with three-dimensional ultrasound before and after undergoing surgical resection of uterine subseptations by hysteroscopy. Measurement of the subseptum's length and width, and total cavity width, were obtained in both groups of women. We created a receiver operating characteristic curve using 7-mm cavity postoperative width change as the reference variable, and subseptation length as the outcome variable. Identifying a new subseptation length that warrants surgical intervention.

Seventy-six women with subseptations and 77 with healthy uteri were included in the study. In the subseptate group, 50 had a subseptum less than 10 mm, and 26 were greater than 10 mm. Uterine and uterine cavity widths were significantly greater than in healthy women. The postoperative cavity width (28 ± 0.9 mm) was correlated with the preoperative subseptum length (R = 0.42; P = .016) and width (R = 0.54; P = .001) and was similar to healthy uteri. The receiver operator characteristic curve identified 5.9 mm (sensitivity = 100%, specificity = 41.4%) as a new threshold length of subseptation, which shows a postoperative cavity adjustment comparable to a subseptation greater than 10 mm.

The relevance of subseptations shorter than 10 mm is currently undetermined and underestimated. Our data indicate a new subseptation cutoff length with postoperative remodeling and statistical relevance similar to longer subseptations. We propose a revision of the recommendations for surgical correction to include the objectively obtained subseptation length greater than or equal to 5.9 mm.