Influence of endogenous estradiol, progesterone, allopregnanolone, and dehydroepiandrosterone sulfate on brain resting state functional connectivity across the menstrual cycle

OBJECTIVE: To [1] study brain resting state functional connectivity (Rs-FC) in a well-characterized sample of healthy women in the mid-follicular and late luteal phases of the menstrual cycle; and [2] examine the correlation between endogenous E₂, P, allopregnanolone, and DHEAS and patterns of Rs-FC across the menstrual cycle. DESIGN: We studied the Rs-FC of the default mode network, salience network, meso-paralimbic network, fronto-parietal network, visual network, and sensorimotor network in the mid-follicular and late luteal phases. Serum levels of E₂, P, allopregnanolone, and DHEAS were correlated to patterns of functional connectivity. SETTING: University medical center. PATIENT(S): Twenty-five healthy women with regular menstrual cycles. INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): Functional connectivity of key brain networks at rest and correlations of hormones to Rs-FC in the mid-follcuar and late luteal menstrual phases. RESULT(S): There were no differences in Rs-FC between the mid-follicular and late luteal menstrual phases using either independent component analysis or seed-based analysis. However, specific correlations between each hormone and patterns of functional connectivity were found in both menstrual cycle phases. CONCLUSION(S): It seems that the association between female sex hormones and brain Rs-FC is menstrual cycle phase-dependent. Future studies should examine the cognitive and behavioral correlates of this association in regularly cycling women.