Anal endosonographic findings in women after vaginal delivery

To estimate a frequency of obstetric anal sphincters defects in women after vaginal delivery.

The study included 102 women, aged from 16 to 40 years (mean age 28.6 years). 28 women had perineal lacerations of 3rd and 4th degree. 22 women had instrumental delivery. Anal endosonography was performed on all participants using BK Medical scanner Pro focus with a 3D endoprobe during the first week after delivery. Starck's classification was used to score sphincters defects.

The endosonographic images were abnormal in 8 out of 102 women (7.8%). Follow-up examinations after 6 weeks confirmed defects in 6 out of 102 women (5.8%). Five women had external anal sphincter torn, and 1 woman had both sphincters, internal and external, defected. Discordance between endosonographic diagnosis of defect and clinical assessment of sphincters continuity was demonstrated in 6 (5.9%) out of 8 initially found, including 2 (1.9%) false endosonographic results and 4 (3.9%) false clinical diagnosis (occult sphincter defects). The endosonography sensitivity and accuracy in sphincter defect diagnostic amounted to 100% and 98%, respectively.

(1) Anal sphincters' tears in symptomatic women are not as frequent as it was believed. (2) The defect diagnosis in the first week after delivery should be verified by a follow-up endosonography in 6 weeks, after regression of the edema and hematoma.