BACKGROUND/AIMS The length of colon is known to be longer in females than in males. In addition, the morphology of colon cancer is different between males and females. The aim of this study was to investigate sex differences in Boston bowel preparation score (BBPS) and colonoscopy insertion time.

METHODS This study retrospectively analyzed medical records and colonoscopy readings of subjects who underwent colonoscopy at Seoul National University Bundang Hospital from March 2015 to April 2018. BPPS was used to evaluate the degree of colon cleanness before colonoscopy. Statistical analysis was performed to compare demographic, clinical, and outcome variables between two groups.

RESULTS The study group consisted of a total of 12,561 patients (6,148 females and 6,413 males). Mean age was 57.8 ± 13.5 years for females and 57.5 ± 13.8 years for males (p = 0.695). Females showed better bowel preparation than males (mean total score: 7.4 ± 1.8 vs. 7.2 ± 1.9, p = 0.001; total score ≥ 6: 5,340 [86.9%] vs. 5,437 [84.8%], p = 0.001; BBPS ≥ 2 for all segments: 5,048 [82.1%] vs. 5,097 [79.5%], p < 0.001). However, cecal intubation time (8.3 ± 6.2 minutes vs. 6.2 ± 6.1 minutes, p < 0.001) and withdrawal time (7.9 ± 3.5 minutes vs. 7.4 ± 3.1 minutes, p < 0.001) were longer in males.

CONCLUSION There were sex differences in BBPS, cecal intubation time, and withdrawal time for subjects undergoing colonoscopy.