Imaging the Brain on Oral Contraceptives: A Longitudinal Study within the Ann S. Bowers Women’s Brain Health Initiative

• Applicant: Dr. Carina Heller
• Subject Area: Biological Psychology and Cognitive Neuroscience
• Term: since 2024
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 544183227

Over 150 million women worldwide use oral contraceptives in the form of the "pill," which are the most commonly prescribed form of birth control in both the United States and European countries. Sex hormones, such as estradiol and progesterone, are important endogenous hormones known to shape the brain throughout the lifespan. Synthetic hormones, such as those found in oral contraceptives, alter the natural hormone balance by lowering the body's own hormone levels. Little is known about how this affects the brain. Research on the effects of hormones on the brain continues to be motivated by the fact that women taking oral contraceptives experience mood swings and struggle with emotional dysregulation, causing up to 10% to stop taking it. At a time when women's reproductive rights are increasingly restricted, it is important to provide acceptable contraceptive methods. It is therefore necessary to better understand the effects of sex hormones on the brain and mood. The aim of this project is to investigate the impact of endogenous and exogenous sex hormones on the brain by extending the single-subject studies of Barth et al. (2016), Taylor et al. (2020), and my preliminary work with the help of the Ann S. Bowers Women's Brain Health Initiative at the University of California Santa Barbara. For this purpose, we have designed a longitudinal study to recruit and examine N = 20 healthy female individuals who wish to start taking oral contraceptives. Functional, structural, and diffusion-weighted MRI measurements will be performed under natural menstrual cycle conditions for five consecutive weeks (study 1) and then again during oral contraception use for five consecutive weeks (study 2). Endogenous hormone profiles, including estradiol, estriol, estrone, progesterone, luteinizing hormone (LH) and follicle-stimulating hormone (FSH), and testosterone (study 1 and study 2), as well as exogenous hormone profiles of ethinylestradiol and progestin (study 2) are collected. In addition, positive and negative affect (PANAS) and anxiety (STAI) are measured daily. The project allows the investigation of macro- and microstructural changes in gray and white matter of the brain under the influence of the natural female cycle and under the influence of exogenous hormones with a daily measurement time resolution using state-of-the-art MRI analyses. This longitudinal approach allows direct comparisons between the natural cycle and hormonally suppressed states within the same individuals, providing meaningful insight into the relationship between sex hormones, brain morphology, and affective states.

• DFG Programme: WBP Fellowship
• International Connection: USA
• Host: Professorin Emily G. Jacobs, Ph.D.