Relationship between collagen autofluorescence of the human cervix and menopausal status

The goal of this study was to evaluate the effect of different menopausal states (pre- and post-) on the endogenous fluorescence of normal cervical tissues. In particular, the average fluorescence as well as the interpatient and intrasample variability in the average fluorescence of the epithelium and stroma were evaluated as a function of pre- and postmenopausal states. High-resolution fluorescence images at excitation-emission wavelengths of 440, 520 nm and 365, 465 nm were obtained from epithelia and stroma of freeze-trapped cervical tissue blocks maintained at -196 degrees C. The fluorescence images were recorded using a low temperature optical scanner. Fluorescence images from a normal sample population (n = 27) were quantitatively analyzed, and the average epithelial and stromal fluorescence intensities were obtained. Data grouped according to menopausal status (pre- vs post-) showed statistically significant differences (P < 0.002) in stromal fluorescence. In particular, the cervical stroma of postmenopausal women showed (1) significantly greater average fluorescence and (2) greater interpatient and intrasample variability in the fluorescence, relative to that of premenopausal women. These results provide evidence for changes in collagen cross-linking with menopause.