Birth control pills may shrink portions of the brain and affect its function, according to a new study.

This can potentially happen because a woman's natural hormones are being suppressed by the Pill's synthetic hormones, which then causes alterations in the brain's structure.

Researchers at the University of California, Los Angeles, conducted a study involving 90 women and found that two key brain regions - the lateral orbitofrontal cortex and the posterior cigulate cortex - were thinner in women who used oral contraception than in those who did not, according to the Huffington Post.

The lateral orbitofrontal cortex is mainly responsible for regulating emotions, while the posterior cigulate cortex is involved with inward-directed thought, and shows increased activity when we recall personal memories and plan for the future.

Anxiety or depression can be brought on by changes in the lateral orbitofrontal cortex in women who are taking the Pill.

"Some women experience negative emotional side effects from taking oral contraceptive pills, although the scientific findings investigating that have been mixed," study leader Nicole Petersen, who is a neuroscientist at UCLA, told HuffPost. "So it's possible that this change in the lateral orbitofrontal cortex may be related to the emotional changes that some women experience when using birth control pills."

Petersen admitted that more research needs to be done in order to know the effect that birth control has on a woman's emotions, as scientists have not determined whether or not the neurological changes are permanent.

This study contradicts earlier findings from 2010 that suggested the Pill thickened brain areas associated with learning, memory and emotion regulation, according to the Huffington Post.

Research on hormonal contraception and brain function is limited and rather inconsistent, and scientists do not have definite answers in terms of the safety of the Pill.

"The possibility that an accepted form of chemical contraception has the ability to alter the gross structure of the human brain is a cause for concern, even if the changes seem benign -- for the moment," wrote neuroscientist Craig Kinsey back in 2010. "In any event, women need to have all of the medical and now, neurobiological, information they can use in informing their personal contraceptive decisions." 

The study was published in the journal Human Brain Mapping.