Sex hormones affect how the brain deals with fear. Some Canadian researchers studied how birth control pills change women’s brains. They found that women who took the pills had thinner brain areas than men. This could make it harder for women to control their emotions. But this effect might go away if they stop taking the pills. The researchers said more research is needed to be sure.
Many women around the world use birth control pills. They have artificial hormones in them. Sex hormones can change how the brain network for fear works.
Canadian researchers looked at how birth control pills affect the brain now and later. They also looked at how natural and artificial sex hormones affect the brain parts for fear.
Alexandra Brouillard, a researcher at Université du Québec à Montréal and first author of the study published in Frontiers in Endocrinology, said, “In our study, we show that healthy women currently using COCs had a thinner ventromedial prefrontal cortex than men. “This part of the prefrontal cortex is thought to sustain emotion regulation, such as decreasing fear signals in a safe situation. Our result may represent a mechanism by which COCs could impair emotion regulation in women.”
Girls and women who take birth control pills are told about some physical changes, like no periods or eggs. But the pills may also change their brains, which keep growing until they are adults. The researchers wanted to know how the pills affect the brain and emotions now and later.
The researchers studied four groups:
- women who took the pills now
- women who took the pills before but not now
- women who never took any hormone pills
- men
They compared these groups to see how the pills changed the brain shape and size and how they made women more or less anxious or stressed than men.
The researchers found that women who took the pills had thinner brain areas than men. This could make it harder for them to control their emotions. But this effect might go away if they stop taking the pills. The researchers said more research is needed to be sure.
There is more to know everything about how birth control pills change women’s brains. The researchers are studying how the age and time of taking the pills matter for the long-term effects. Teenage girls who take the pills when their brains are still growing may have different outcomes.
The researchers said their study had some problems. They can’t know for sure that the pills cause the brain changes. They can’t apply their results to all women. They can’t tell how the brain changes affect the emotions and thoughts.
Brouillard said, “The objective of our work is not to counter the use of COCs, but it is important to be aware that the pill can affect the brain. We aim to increase scientific interest in women’s health and raise awareness about early prescription of COCs and brain development, a highly unknown topic.”
The study had some limitations. It could not prove that the pills caused the brain changes. It could not apply the results to all women. It could not tell how the brain changes affected the behavior and psychology of the women. The study said that more studies are needed to understand the impact of contraceptive pills on women’s brains and emotions.
Journal reference:
- Alexandra Brouillard, Lisa-Marie Davignon, et al., Morphologic alterations of the fear circuitry: the role of sex hormones and oral contraceptives. Frontiers in Endocrinology. DOI: 10.3389/fendo.2023.1228504.