According to Lifezette:
Since they debuted in the 1960s, oral contraceptives have become the most commonly used form of birth control. But now a new generation of users is questioning the pill’s impact on mental health.
The pill has had many makeovers through the years, with some varieties containing both female hormones, progesterone and estrogen, and some only progesterone. The oral version has been joined by implanted devices and injections. Either way, the combination of hormones interfere with ovulation, or the production of an egg from a woman’s ovaries.
Physical side effects such as bleeding and even cancer have been researched, but a recent study about a possible link between the pill and depression and anxiety has many rethinking its use. The study look at 1 million Danish women who used hormone-based contraception for an average of six years.