Variability of apparent diffusion coefficient in the brain in women during follicular and luteal phases of the menstrual cycle

Purpose To investigate the variability of apparent diffusion coefficient (ADC) in the brain in women during follicular and luteal phases of the menstrual cycle. Methods The present study included 32 females of reproductive age with regular menstruation. The participants were divided into two groups as group 1: females in the follicular phase, and group 2: females in the luteal phase. The regions of interest were manually drawn on the structures of the T2-weighted images (frontal gray and white matter, parietal gray and white matter, temporal gray and white matter, occipital gray and white matter, cerebellar gray and white matter, caudate nucleus, putamen, thalamus, internal capsule, pons, cerebrospinal fluid (CSF) in the frontal and in the occipital horn of the lateral ventricle and CSF in the middle part of the lateral ventricle). ADC values were averaged for each patient. We used Kruskal-Wallis ANOVA for more than two groups but used Mann Whitney U test for comparison of ADC values between the group of 18 females in the follicular phase and the group of 14 females in the luteal phase. Results No statistically significant differences were observed among the groups in terms of the ADC value of each neuroanatomic structure that was evaluated. Conclusion We did not determine a significant difference among volunteers at the two different phases of the menstrual cycle in terms of ADC values measured from different regions of the brain. However, although not statistically significant, ADC values measured from almost all parts of the brain were higher at the luteal phase than at the follicular phase.