title: Effects of gender and menstrual cycle on colonic transit time in healthy subjects.
abstract: BACKGROUND
  Measuring colonic transit time (CTT) by the radio-opaque marker method is simple, widely available and important for the diagnosis of slow transit constipation. Moreover, the effects of gender and menstrual cycle on CTT remain controversial. Thus, in this study, we examined the effects of gender and menstrual cycle on CTT in healthy subjects.
  
  
  METHODS
  We measured CTT in 42 healthy subjects (21M, 21F) by using a radio-opaque marker, Kolomark. Two simple abdominal radiographs were taken on the 4th and 7th days. Average daily intake of dietary fiber and menstrual history were surveyed.
  
  
  RESULTS
  The mean CTT of the 42 healthy subjects was 26.5 +/- 19.4 hours. The mean CTT was not significantly different between the male and female subjects (22.3 +/- 16.1 h vs. 30.1 +/- 21.4 h, p > 0.05). However, the mean CTT of 11 female subjects in the luteal phase was significantly longer than that of 10 female subjects in the follicular phase (40.9 +/- 19.0 h vs. 20.6 +/- 19.2 h, p < 0.05). Serum progesterone level, age, BMI, and the average daily intake of dietary fiber did not correlate with CTT.
  
  
  CONCLUSIONS
  The effects of the menstrual cycle should be considered in interpreting CTT in young women.
authors: Department of Internal Medicine, College of Medicine, Ewha Womans University, Seoul, Korea.
authors: Hye-Kyung
authors: HK
authors: Jung
authors: Doe-Young
authors: DY
authors: Kim
authors: Il-Hwan
authors: IH
authors: Moon
mesh_terms: D000328:Adult; D003106:Colon / Q000000981:diagnostic imaging / Q000503:physiopathology*; D003248:Constipation / Q000000981:diagnostic imaging / Q000503:physiopathology; D003287:Contrast Media; D005260:Female; D005772:Gastrointestinal Transit / Q000502:physiology*; D006801:Humans; D008297:Male; D008597:Menstrual Cycle / Q000502:physiology*; D008875:Middle Aged; D011860:Radiography, Abdominal; D012737:Sex Factors
chemical_list: D003287:Contrast Media