Birth control pills may increase a woman's risk of developing glaucoma, a leading cause of blindness, a new study found.

Researchers looked at data regarding more than 3,400 women aged 40 and older, all of whom completed a vision and reproductive health questionnaire and underwent eye exams as part of a survey administered by the Centers for Disease Control and Prevention.

Presented at the 117th Annual Meeting of the American Academy of Ophthalmology, the study found that women who reported using oral contraceptives of any kind for more than three years were twice as likely to report having been diagnosed with glaucoma.

While the study merely addresses a correlation, the researchers argue that, based on the results, use of birth control pills may be considered as part of the risk profile for a patient when screening for the eye disease.

"This study should be an impetus for future research to prove the cause and effect of oral contraceptives and glaucoma," said Dr. Shan Lin, lead researcher and professor of clinical ophthalmology at the University of California San Francisco. "At this point, women who have taken oral contraceptives for three or more years should be screened for glaucoma and followed closely by an ophthalmologist, especially if they have any other existing risk factors."

According to Dr. Jennifer Ashton, ABC News' senior medical contributor and a board-certified obstetrician and gynecologist, women who are on the pill should not panic.

"This study does not demonstrate cause and effect between use of the pill and development of glaucoma," Ashton told the news outlet. "There are numerous qualifying issues: the study's authors state that 'long-term use might be a potential risk factor' and should be considered especially when other risk factors are present.'"

Glaucoma is characterized by a group of eye conditions that together result in damage to the optic nerve. Symptoms include gradual loss of peripheral vision, eye pain, halos around lights and blurred vision, depending on the type of glaucoma. According to Mayo Clinic health officials, early diagnosis and treatment can minimize or prevent damage to the nerve and limit vision loss.