Pelvic floor muscle injuries in women with a history of Caesarean section.

Objective: The aim of the paper is to determine the prevalence of levator ani muscle injuries and identify risk factors among women undergoing vaginal birth after Caesarean section (VBAC) compared to those with elective repeat Caesarean section (ERCS).

Material and methods: This prospective observational comparative study was conducted at the 2nd Clinic of Gynaecology and Obstetrics of FM CU and UN Bratislava. Women with a history of one Caesarean section were included in the study. They were divided into those who had a successful VBAC and those who delivered by ERCS. The mothers underwent a 3D/4D ultrasound examination of the pelvic floor muscles 3‒5 days after childbirth. The study evaluates the frequency and risk factors of avulsion injury of the levator ani muscle (LAM) in a group of 46 women after a successful vaginal delivery after a previous Caesarean section and 32 women after ERCS using 3D/4D transperineal ultrasound examination of the pelvic floor.

Results: A total of 78 women were included in the study, 46 after VBAC and 32 after ERCS. In the first group, we recorded LAM avulsion injury in 13 cases (28.3 %); in the post-ERCS group, we did not record this injury (p < 0.0001). We also found an overdistended hiatal area (21.0 vs 19.4 cm2) and a more frequent occurrence of the area exceeding 25 cm2 (21.3 % vs 6.2 %, p = 0.0340) which was approaching the statistical significance. In the first group, we identified an increase in weight during pregnancy to 15 kg and a neonatal birthweight of 4,000 g or higher as risk factors for LAM injury.

Conclusion: In the group of women with VBAC, there is a statistically significant risk of LAM avulsion and a higher occurrence of the overdistended area of ​​the hiatus urogenitalis, especially in women with larger foetuses and in those who experienced greater weight gain during pregnancy (Tab. 3, Ref. 50). Text in PDF www.elis.sk Keywords: pelvic floor, levator ani muscle avulsion, vaginal birth after Caesarean section.