Transvaginal sonography in the detection of retained products of conception after first-trimester spontaneous abortion

Abstract

Purpose: The aim of this study was to assess the use of transvaginal sonography to detect retained products of conception after first-trimester spontaneous abortion.

Methods: All women who arrived at our hospital with spontaneous first-trimester abortions were included in this study and underwent transvaginal sonography. A sonographic diagnosis of "incomplete abortion" was based on a bilayer endometrial thickness of more than 8 mm. The final diagnosis of complete or incomplete abortion was based on the histopathologic findings at dilatation and curettage. The sensitivity and specificity of both clinical and sonographic examinations for detecting products of conception were assessed.

Results: A total of 113 women were recruited, and 14 were excluded for various reasons. Among 52 women with a clinically incomplete abortion, only 50% had retained products of conception. The use of transvaginal sonography resulted in a 29% (15/52) reduction of surgical intervention in these women. On the other hand, 30% (14/47) of women with a clinical diagnosis of complete abortion had retained products of conception. The sensitivity and specificity of cervical status for detecting retained products of conception were 65% and 56%, respectively, whereas the overall sensitivity and specificity of transvaginal sonographic examination (bilayer endometrial thickness 8 mm or less) were 100% and 80%, respectively.

Conclusions: Transvaginal sonography is a useful supplement to clinical assessment in women who experience a spontaneous first-trimester abortion. If this modality is used to assess the uterine cavity, the cervical status can be ignored. Use of transvaginal sonography should reduce unnecessary general anesthesia and uterine curettage.