Patient characteristics
In total, 3545 consecutive patients who underwent pelvic MRI from July
2018 to June 2019 were reviewed. Of these patients, 2931 met the
exclusion criteria, and 614 cases remained in the final analysis (Fig.
2). The study sample had a median age of 43 [range: 17 to 76] years
and a median body mass index of 22.4 [range: 15.6 to 38.8]
kg/m2. In total, 63.5% (390/614) of the patients had
laparoscopic or transabdominal surgery records. The enrolled patients
were stratified by age, with 120 patients aged ≤ 30 years, 282 patients
aged between 31 and 49 years, and 212 patients aged ≥ 50 years old. The
differences in height, weight, BMI and position of uterus among these
three groups were limited as shown in Table S1. However, the parity
times significantly differed among the groups (p < .001). The
women aged ≥ 50 years had the highest rate of multiparity (49.1%,
104/212) and highest rate of vaginal delivery (92.9%, 197/212) but the
lowest rate of nullipara (0.9%, 2/212). The women aged between 31 and
49 years were mostly primiparous (59.6%, 168/282), and the vaginal
delivery rate was 52.8% (149/282), while the women aged ≤ 30 years were
mostly nulliparous (79.2%, 95/120), and the vaginal delivery rate was
only 12.5% (15/120). These findings are presented in Table S1.