Vesicouterine adherence is independent of the degree of villi implantation: A retrospective case-control study

Abstract

Background: The presence of differences between the clinical and histological classification of PAS hinders an accurate depiction of the extent of the maternal condition. None of the existing histological classification criteria are based on and correlate with surgical difficulty, morbidity risk, or maternal outcome. Methods: We conducted a case-control study of data of all PAS cases between January 2017 and December 2021 at Dr. Soetomo General Hospital, Surabaya, Indonesia. Uterine dehiscence and any cases with incomplete data were excluded from the study. After surgery, the area of abnormal adherence was marked using small pins for histological analysis. The histopathology specimens were immersed in using Hematoxylin Eosin (HE). PAS cases were divided into three groups depending on the depth of villi: accreta, increta and percreta. Primary outcome was the vesicouterine adherence. Secondary outcomes were intraoperative topography, and surgical outcome. Results: Three hundred sixty-three cases were included for analyses. Our cohort comprised of 99 accreta cases, 246 increta cases and 18 percreta cases. Estimated blood loss was significantly higher in the high-grade PAS (increta and percreta) groups than in the low-grade PAS (accreta) group (2851.0 + 2437.7 mL vs 1970.8 + 1315.8 mL; p < 0.001). Sixty-five (17.9%) cases of vesicouterine adherence were observed. This was associated with higher odds of caesarean hysterectomy (adjusted odds ratio [Adj OR] 30.77 (95% CI 12.52–75.62; p < 0.001) and bladder injury (Adj OR 7.19; 95% CI 1.94–26.64; p = 0.003) but not estimated blood loss (> 2500 mL) (Adj OR 1.06; 95% CI 0.52–2.16; p = 0.87). Cases with bladder injury had a higher estimated blood loss (p = 0.012) and concomitant caesarean hysterectomy (p < 0.001) compared to those without bladder injury. The depth of villi implantation was associated with higher blood loss (> 2500 mL) (p = 0.046) but not bladder injury (p = 0.442) and vesicouterine adherence (p = 0.503). Conclusions: Vesicouterine adherence is not associated with the depth of villi implantation, but rather with the presence of fibrosis between the bladder and uterus. These adhesions also correlated to iatrogenic bladder injuries.