Do Birth Control Pills Affect Your Mood? Scientists Can’t Agree

Earlier this month, the surprising findings of some new research were presented at a conference. At the virtual European Congress of Psychiatry, Elena Toffol and her team from the University of Helsinki in Finland reported that they had found that attempted suicide rates were lower in women who used hormonal contraception compared to those who didn’t. In fact, the latter group were almost 40 percent more likely to attempt suicide than the former, they reported. 

These findings (which have not yet been peer-reviewed) might be the opposite of what you’ve heard—or experienced: Doesn’t hormonal birth control have a reputation for exacerbating mental illness? Your confusion would be forgiven. Perhaps you recall headlines from 2017, when a Danish study found that hormonal contraception was linked with an increase in attempted suicides. 

This giant contradiction is but one of many in the years of research that has tried to answer the question of whether hormonal birth control causes psychological side effects—and the jury is still out. In September 2016, The New York Times published an article with the headline “Contraceptives Tied to Depression Risk.” Six months later, the same publication came out with a piece headlined “Birth Control Causes Depression? Not So Fast.” 

Oral contraceptives, which first came on the market more than 60 years ago, are astonishingly popular. Over 100 million women worldwide are estimated to be current users. The pill, as the medication is known, comes in two forms: a progesterone-only version and a combined estrogen and progesterone version. Both contain synthetic hormones designed to stop or reduce ovulation—the release of the egg from the ovary. 

But the decision to use hormonal birth control is not always borne out of a desire to remain unpregnant. The name is rather a misnomer; a more fitting designation would be “hormone medication, often used as birth control.” Hormonal contraception is prescribed for a veritable smorgasbord of conditions, including migraines, cystic acne, chronic menstrual pain, polycystic ovary syndrome (PCOS), and endometriosis. 

Fears about the pill’s psychological side effects fall into a growing trend that has emerged in recent years: a widespread distrust of hormonal contraception and wariness of its downsides, now that the satisfaction of hard-won victories for women’s self-determination have worn off. A flurry of books questioning how hormonal birth control negatively affects its users have been published in the past decade. Coming out as the top concern are mood changes, which are reported to be the number one reason women choose to go off the pill.

But we don’t yet have a clear answer on whether the link between the pill and mood is real. The biggest problem is that most studies to date have been cross-sectional in design, meaning they involve taking a group of women who are using the pill and comparing them to a group who aren’t using it. “It doesn’t take into account that women who tried the pill and had negative mood effects or sexuality negative effects would come off it,” says Cynthia Graham, a professor in sexual and reproductive health at the University of Southampton and editor-in-chief of The Journal of Sex Research. “That, to me, is one big reason why it’s difficult to answer the question.” This is called the survival bias, or healthy-user bias.