Abstract
Background: Natural childbirth is regarded as the most frequent cause of anal sphincter defects. The majority of obstetric injuries are detectable only by anal endosonography (AES), in from 6.8% to 35% of women after vaginal delivery.
Purpose: To evaluate prospectively anal sphincters in primiparous women in the first days after delivery to estimate the prevalence of anal sphincter defects and to correlate selected risk factors with the recognized injuries.
Material and Methods: A total of 112 consecutive primiparous women aged 19–40 years (mean 29.3 years) underwent three-dimensional (3D) AES with the use of a BK Medical scanner Profocus 2202 in the first weeks after delivery.
Results: Twelve tears (10.7%) in the perineum, including three extending to anal sphincters (2.6%) were found on AES. As many as 86 (76.8%) women had medio-lateral episiotomies due to the practice pattern in our hospital or as a consequence of obstetric factors. The statistical analysis did not prove a significant association between diagnosed injuries and episiotomy (P=0.73), nor a traumatic effect of epidural anesthesia, fetus head circumference ≥34 cm, or birth weight ≥3525 g.
Conclusion: Anal sphincter tears following childbirth were found in only 2.6% of primiparous women, suggesting that vaginal delivery might not imply high risk of pelvic floor damage as has previously been assumed. The results do not confirm that medio-lateral episiotomy is conducive to obstetric anal sphincter defects.
Declaration of interest: The authors report no conflicts of interest. The authors alone are responsible for the content and writing of the paper.