BECONTRA by Belinda Pletzer

Brain effects of contraceptives: How birth control pills affect the female brain

Birth control pills have been on the market for 60 years now and are used by 150 million women worldwide. Particularly, the use of birth control pills increases among adolescents. While the major target of birth control pills are hormone axes regulated by the brain, the effects of birth control pills on the brain have been widely ignored. That is even more surprising, since psychological side effects of birth control pills have been described since the 1960’s and are the most common reason for discontinuation of contraceptive treatment. Furthermore, there is accumulating evidence from both animal and human studies, that endogenous sex hormones affect the brain, both structurally and functionally. Since birth control pills contain synthetic sex hormones that target the same receptors as endogenous sex hormones, it is reasonable to assume effects of birth control pills on the female brain. Yet up to date, we know next to nothing about these effects.

The ERC Starting Grant project BECONTRA (Brain effects of contraceptives) seeks to close this gap of knowledge, by characterizing neuronal, emotional and cognitive effects of birth control pills and their reversibility upon withdrawal in a longitudinal design. In order to do so, we will apply a multi-modal neuroimaging paradigm assessing brain structure, function and connectivity in girls and women who intend to start contraceptive treatment. In a first step, the participants will be tested once before they start contraceptive treatment, as well as after three and six months of contraceptive treatment. In a second step, the participants will be followed up upon after discontinuation of contraceptive treatment to assess the reversibility of effects. The effects will be compared between the most commonly used contraceptives and between adolescent and adult pill-users.
Thereby we seek to answer the following research questions:

1. Does the brain change under the influence of birth control pills and are these changes reversible?

2. Are there cognitive changes associated with the effects of birth control pills on the brain?

3. Do different types of pills cause different effects in the brain?

4. Do the effects of birth control pills on the brain interact with brain development during adolescence?

5. Can differences in the brain explain why some women experience psychological side effects on birth control pills, while other women experience beneficial effects?

This project is the first project to address these questions systematically in a well-powered sample with a longitudinal design. The answers to these questions will bring us an important step forward in providing women and medical professionals with the relevant information to choose the ideal contraceptive for each woman on an individual basis.