Prospective evaluation of the incidence of uterine vascular malformations developing after abortion or delivery.

STUDY OBJECTIVE: To describe the incidence of uterine vascular malformations (UVMs) including uterine arteriovenous malformations (AVMs) in patients after abortion or delivery and in outpatients. DESIGN: Prospective study (Canadian Task Force classification II-3). SETTING: Fukushima Red Cross Hospital. PATIENTS: Six patients with a UVM including 1 with an AVM. INTERVENTIONS: Clinical screening of patients using transvaginal color Doppler ultrasonography between April 2010 and March 2012. MEASUREMENTS AND MAIN RESULTS: The incidence of UVM developing after abortion or delivery or in outpatients was prospectively evaluated using transvaginal color Doppler ultrasonography. From 959 patients, we identified 6 (0.63%) with UVMs, including 1 (0.10%) with a uterine AVM. Specifically, we detected UVMs in 4 of 77 patients (5.2%) after abortion, 1 of 458 patients (0.22%) after delivery, and 1 of 424 outpatients (0.24%). Four patients after abortion and 1 after delivery reported mild symptoms, which were treated conservatively; however, the outpatient had a severe uterine AVM, which was confirmed via 3-dimensional computed tomography angiography. CONCLUSION: The incidence of UVMs was relatively higher, in particular in the patients after abortion, and was significantly higher than that in postpartum or outpatient groups. Therefore, it is important to consider the possibility of UVMs in any patient with episodes of unexplained uterine bleeding and to perform follow-up analysis using color Doppler ultrasonography. Such an approach will facilitate accurate diagnosis and lead to appropriate clinical management to prevent unnecessary dangerous repeat curettage, which might induce profuse uterine bleeding.