Sonographic characteristics of the uterine cavity following first-trimester uterine evacuation

Objective To characterize the sonographic appearance of the uterine cavity after first-trimester uterine evacuation and to follow the evolution of these findings in an attempt to reduce the number of unnecessary surgical interventions following evacuation. Methods: We studied retrospectively the sonographic characteristics of the uterine cavity in 599 women, 5-8 days after first-trimester uterine evacuation. The patients were grouped according to the sonographic appearance of the uterine cavity. Patients with abnormal sonographic patterns were followed weekly until sonographic resolution. Results: Group 1 included 351 (58.6%) women with normal endometrium; Group 2 included 130 (21.7%) women with hypoechoic endometrial content only; Group 3 included 69 (11.5%) patients with mixed type (hypoechoic and hyperechoic) endometrial content; Group 4 included 49 (8.2%) patients with hyperechoic endometrial content only. The time needed until the uterine cavity was considered normal was significantly longer in Group 4 (median, 12 days) compared with Groups 3 and 2 (8 and 9 days, respectively, P < 0.0001). The duration of vaginal bleeding after the surgical procedure was longer in Group 4 (median, 10 days) compared with Groups 3, 2 and 1 (9, 7 and 5 days, respectively, P < 0.0001). Clinically, the patients were divided into two groups: asymptomatic (575 patients) and symptomatic (24 patients). The thickness of the abnormal endometrial content in the asymptomatic patients gradually decreased until normalization, around the time of menstruation. There was no such change in the symptomatic patients, who eventually needed surgical intervention. Conclusions: An abnormal intrauterine sonographic pattern 5-8 days following first-trimester uterine evacuation is common and usually resolves spontaneously around menses. Therefore, in asymptomatic patients, we recommend a conservative approach.