Birth Control Pills May Make Women Struggle With More Complex Emotions, Study Finds

Many millennial women spend a significant portion of their adult life taking oral contraceptives to prevent pregnancy. Birth control pills can help control acne, heavy periods, and endometriosis, and they also reduce the risk of developing some cancers. But those little pills can also cause difficult side effects for some women, like weight gain, anxiety, and high blood pressure. And this month, a new study out of the University of Greifswald in Germany found something else we might need to worry about: Birth control pills could be blurring your emotional recognition.

The new study, just published in Frontiers in Neuroscience, builds on previous research about the psychological consequences of taking oral contraceptives. We already know women who take oral contraceptives tend to choose different men1 than they would if they weren't taking the pills, and birth control can significantly affect some women's moods2. But this new study goes a step further by questioning how oral contraceptives affect our social and emotional intelligence.

In the new study, researchers looked at two similar groups of healthy women between ages 18 and 35, some who used oral contraceptives and some who did not. At first, the researchers didn't find any dramatic psychological differences between the two groups of women.

"If oral contraceptives caused dramatic impairments in women's emotion recognition, we would have probably noticed this in our everyday interactions with our partners," said lead study author Dr. Alexander Lischke in a news release. "We assumed that these impairments would be very subtle, indicating that we had to test women's emotion recognition with a task that was sensitive enough to detect such impairments. We thus used a very challenging emotion recognition task that required the recognition of complex emotional expressions from the eye region of faces."

Lischke's team found that both groups were equally good at recognizing easy, black-and-white facial expressions on a computer during an emotional recognition test. However, the women who took oral contraceptives were 10 percent worse on average than non-users at interpreting emotions when the facial expressions became more complex. In other words, the women using oral contraceptives were more likely to misinterpret social cues relating to recognizing more nuanced, complicated emotions. They had an especially difficult time reading complex negative facial expressions, according to the study.

What could be causing this subtle difference? It has to do with the hormones these contraceptives manipulate. Hormones are chemicals that carry messages from your brain to the rest of your body, helping to control and regulate basic human functions like eating and sleeping, as well as more complex processes like your emotions and mood. According to Lischke and his team, all women experience natural, cyclic variations of hormones like estrogen and progesterone levels throughout the month. Most importantly, during certain times in your menstrual cycle, estrogen and progesterone hit levels that push you to be more emotionally attuned to others. (Evolutionarily, it's useful for you to be more aware of someone else's emotions—especially your significant other's—around the times you're most fertile.) But oral contraceptives usually suppress estrogen and progesterone levels. Without normal levels of those hormones in their system, some women may struggle to interpret complex emotional cues.