Since the beginning of this project we have invited girls and women, who want to start or stop using birth control pills to take part in our study and complete brain scans prior to starting/stopping combined oral contraceptive treatments and every 3 months after that. While data acquisition is still ongoing, we were able to adress the following questions from existing data sets and control participants:
(i) Which brain paramters are sensitive to hormonal changes during the tasks utilized in this study?
(ii) Which brain parameters relate to adverse mood effects during combined oral contraceptive treatment?
(iii) Which brain parameters relate to oral contraceptive treatment duration?
Overall, the brain parameters most sensitive to hormonal changes and birth control pills appear to be measures of brain connectivity. Thus, steroid hormones, whether endogenous or exogenous modulate how different brain areas communicate with each other rather than just the activity of specific brain areas.
Mental health has been convincingly linked to the interplay between three brain networks, which have been linke to self-referential processing, attention and inhibitory control. In the period covered by this report we were able to demonstrate that the interplay between those three networks is not only modulated by endogenous ovarian hormones but also by birth control pills. In women, who reported adverse mood symptoms during combined oral contraceptive use, changes in brain connectivity were related to mood lability. This raises the question, whether these changes in large-scale network connectivity are specific to women who experience adverse mood symptoms and whether women, who experience beneficial effects show different brain connectivity patterns.
Oral contraceptive treatment duration was also related to changes in brain connectivity during verbal and spatial tasks on the one hand and face processing on the other hand. While these associations were irrespective of the contraceptive type for verbal and spatial tasks, associations between oral contraceptive treatment duration and brain connectivity during face processing were mostly observed for combined oral contraceptives containing an androgenic progestin, i.e. levonorgestrel.
